Method and device for colouration of substrates

Abstract

A method and system for colouring a substrate or applying a dispersion to the surface of a substrate. The method may comprise applying a colourant to a substrate and subsequently exposing the substrate to an atmospheric plasma to fix the colour to the substrate. The colourant can be fixed to the substrate by a coating fluid delivered to the substrate after application of colour, and in which the coating fluid may be polymerised by the plasma.

Description

METHOD AND DEVICE FOR COLOURATION OF SUBSTRATES TECHNICAL FIELD

[0001] The present invention relates to colouration of substrates which can be fixed with a secondary treatment method, such as curing, plasma exposure, radiation exposure and exposure to a chemistry or monomer. More particularly, the present invention may relate to colouration and fixation of the colour with plasma enhanced chemical vapour deposition techniques. BACKGROUND

[0002] The treatment of textile materials, fibres, yarns, and fabrics, involves a chemical process for finishing and the application of colour with printing and dyeing processes. These processes are integral to textile production along with spinning, weaving, or knitting, encompasses pretreatment, dyeing, printing, and finishing stages.

[0003] The quality of dyeing and finishing is important for substrates such as textiles and can have a large influence on the value and function of these materials. Dyeing and finishing process of clothing fabric, in conventional methods generally requires a first step of singeing; second step of desizing; a third step bleaching; a fourth step heat setting; a fifth step dyeing; and a sixth step finishing, a seventh step of tentering and shaping. The general chemical auxiliaries used in the dyeing and finishing processes are common in the market.

[0004] However, these processes are generally resource intensive and may require a large amount of water usage and contamination, chemical usage, energy consumption, waste generation, and air pollution. Generally, the dyeing process requires large quantities of water, which can lead to contamination of water bodies due to the discharge of untreated or inadequately treated wastewater containing chemicals, dyes, and heavy metals. Many dyes and chemicals used in dyeing are toxic and hazardous to both human health and the environment. Their release into ecosystems can disrupt aquatic life and pollute soil and groundwater. Further, dyeing and finishing processes are energy-intensive, contributing to overall carbon emissions and exacerbating climate change.

[0005] The textile industry also generates significant amounts of solid waste, including leftover dyes, chemicals, and byproducts from the dyeing process. Proper disposal or treatment of these wastes is often inadequate, leading to environmental contamination. The production of synthetic dyes and chemicals used in dyeing and finishing textiles relies on non-renewable resources such as petroleum. In addition, some processes within dyeing and finishing, such as drying and curing, can release volatile organic compounds (VOCs) and other pollutants into the air, contributing to air quality issues.

[0006] Furthermore, the scale for dyeing and finishing processes are generally preferred to handle several tonnes of material to be the most efficient, with smaller treatment volumes being less viable or desirable due to equipment usage times and overall expense for handling smaller volumes relative to larger volumes of materials.

[0007] Other treatment and finishing processes may also impact the properties of an untreated material, such as breathability, handfeel, fibre strength, tearing strength, and colourfastness properties. These properties are also different when comparing synthetic and organic materials. Further, processes to treat organic and synthetic materials can be vastly different which may also lead to different equipment for treatment of these materials and different recipes and chemistries for successfully treating the materials.

[0008] Plasma-Enhanced Chemical Vapor Deposition (PECVD) is a technique used for thin film deposition techniques in a number of industries, including semiconductor manufacturing and optics. The use of this process is generally within a low pressure environment such that coatings can be applied with tight tolerances. However, the use of these low-pressure environments slows down production speeds and also introduces added expense from processing time increases and cost for vacuum systems and other related cryo-trap or fluid capture devices associated with the process.

[0009] In view of the above, it may be desirable to provide for a process which may ameliorate at least one of the above issues with conventional processing.

[0010] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field. SUMMARY

[0011] PROBLEMS TO BE SOLVED

[0012] It may be advantageous to provide for an improved process for applying a dispersion to a textile.

[0013] It may be advantageous to provide for an alternative process for applying a colourant to a textile.

[0014] It may be advantageous to provide for a means for reducing waste water for textile colouring and finishing processes.

[0015] It may be advantageous to provide for a means for reducing energy consumption for textile colouring and finishing.

[0016] It may be advantageous to provide for a means for reducing chemistry consumption for textile colouring and finishing.

[0017] It may be advantageous to provide for a means for reducing air pollution consumption for textile colouring and finishing.

[0018] It may be advantageous to provide for a means for reducing energy consumption for textile colouring and finishing.

[0019] It may be advantageous to provide for a system suitable for colouring and / or finishing a textile which removes water from the application process.

[0020] It may be advantageous to provide for a more sustainable method of applying colour or pigment to a substrate.

[0021] It may be advantageous to provide for an improved method of colour fixation without the requirement of a stenter.

[0022] It may be advantageous to provide for a method for applying colour to both synthetic and organic materials with the same processing system.

[0023] It may be advantageous to provide for a method for applying a finish to both synthetic and organic materials with the same processing system.

[0024] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

[0025] MEANS FOR SOLVING THE PROBLEM

[0026] In a first aspect there may be provided a method for colouring a substrate. The method may comprise the steps of applying a colourant to the substrate, exposing the substrate to a plasma to fix the colour to the substrate; and wherein the colourant may be fixed to the substrate by a coating fluid delivered to the substrate after application of colour.

[0027] Preferably, the colourant may be delivered to the substrate in a dispersion. Preferably, the dispersion may be at least partially removed before being exposed to a plasma. Preferably, fluids of the dispersion may be removed leaving the colourant of the dispersion on the substrate before being exposed to a plasma. Preferably, the method may further have the step of heating the substrate after applying the colourant to remove moisture from the substrate. Preferably, the method may have the step of supplying a monomer to the plasma such that the monomer may be polymerised to form a polymer over the colourant. Preferably, the polymer may bond to the substrate and the colourant. Preferably, the coating fluid may be polymerised by the plasma to form a coating and thecolourant may be at least partially embedded within the coating. Preferably, the coating may be of a thickness which encapsulates the colourant within the coating. Preferably, the plasma may be formed at a pressure between 95kPa to 110kPa. Preferably, the plasma may be generated with a working gas which may include at least two of the following gases: argon, oxygen and nitrogen.

[0028] In a further aspect, there may be provided a system for applying a colourant to a substrate. The system may comprise a processing line with a colourant application device. Arranged down the processing line relative to the colouration application device may be a plasma module, and wherein the colourant application device may be adapted to apply a colourant to the textile and the plasma module may be used to apply a coating to the colourant to fix said colourant to the substrate.

[0029] Preferably, between the colourant application device and the plasma module the processing line may include a heating system adapted to evaporate dispersion from the substrate. Preferably, the colourant application device may be selected from the following group; a digital printer, an inkjet printer, a digital print head or series of heads, a textile printer, a hydraulic spray device, an atomisation spray device, and an electrostatic applicator. Preferably, the plasma module may be operable in the pressure range of 95kPa to 105kPa. Preferably, the plasma module may be provided with a first electrode and a second electrode, in which the first and second electrodes may be arranged to be parallel, in which the electrodes may have a dielectric material. Preferably, the plasma module may be adapted to apply a functional finish. Preferably, the plasma may physically modify a surface texture of the colourant on the textile.

[0030] In the context of the present invention, the words “comprise”, “comprising” and the like are to be construed in their inclusive, as opposed to their exclusive, sense, that is in the sense of “including, but not limited to”.

[0031] The invention is to be interpreted with reference to the at least one of the technical problems described or affiliated with the background art. The present aims to solve or ameliorate at least one of the technical problems and this may result in one or moreadvantageous effects as defined by this specification and described in detail with reference to the preferred embodiments of the present invention. BRIEF DESCRIPTION OF THE FIGURES

[0032] Figure 1 illustrates a side view of an embodiment of a system for application and fixation of colour;

[0033] Figure 2 illustrates a side view of an embodiment of an entry web handling device for a system;

[0034] Figure 3 illustrates a side view of an embodiment of an exit web handling device for a system;

[0035] Figure 4 illustrates a side view of an embodiment of an application device adapted for treating a substrate and a heating apparatus;

[0036] Figure 5 illustrates a side view of an embodiment of a series of plasma segments which house a plurality of plasma devices;

[0037] Figure 6 illustrates a side view of an embodiment of a plasma module which may be suitable for a plasma segment; and

[0038] Figure 7 illustrates an isometric view of an embodiment of a plasma segment of a system;

[0039] Figure 8 illustrates an embodiment of a process flowchart for treating a substrate with a dispersion;

[0040] Figure 9 illustrates an embodiment of a process flowchart for treating a substrate with a dry pigment.DESCRIPTION OF THE INVENTION

[0041] Preferred embodiments of the invention will now be described with reference to the accompanying drawings and non-limiting examples.

[0042] Features 1 Substrate 10 System 20 Frame 30 Seal 100 Web handling entry apparatus 110 Web handling exit apparatus 115 Unwinder 120 Rewinder 125 Rollers 130 Tensioner 135 Monitoring device 150 Tensioning segment 200 Atmosphere control segment 210 Air lock 215 System extraction 300 Application segment 305 Application module 310 Dispersion application device 311 Powder application device 315 Primer application device 320 Reservoir 400 Heating segment 410 Heating module 415 Heating element 420 Heating extraction 500 Plasma segment501 Segment upper 502 Segment lower 510 Plasma module 515 Electrodes 520 Dielectric 525 Metal conductor 530 Manifold 540 Electrode cooling 600 Power supply 610 Cooling pumps 620 Cooling reservoir 700 Dispersion process 710 Step 1 720 Step 2 730 Step 3 740 Step 4 750 Step 5 760 Step 6 770 Step 7 800 Pigment process

[0043] System

[0044] Referring to Figure 1 there is illustrated an embodiment of a system 10 of the present disclosure. The system 10 comprises a plurality of segments which are used to treat a substrate 1. The segments 100, 200, 300, 400, 500 are connected with a respective seal 30 between each adjacent segment. Each segment comprises a frame 20 which houses the electronics, power supply 600, and fluid systems (if applicable) for said segment. The segments which may be within a system may be selected from the group of; an unwinder, a web handling device, a tensioner, a primer segment, an entry segment, a pre-treatment segment, an application segment, a heating segment, a plasma segment, an exit segment,and a rewinder. It will be appreciated that any number of segments listed, in any order and any quantity may be included within the system 10. For example, a system may use a primer segment before the application segment, and also before the plasma segment after the application segment. Other segments may also form part of a larger system, but will contain one or more segments disclosed herein.

[0045] A web handing entry apparatus 100 is positioned at the start of the system. This apparatus 100 is adapted to unwind a substrate 1 from an unwinder 115. The substrate is then provided to a tensioning segment 150 with a plurality of rollers 125 which can impart a desired tension to a substrate 1. The tensioning segment 150 may be fitted with one or more monitoring devices 135 which can determine at least one of; the movement speed of the substrate, the tension of a substrate and thickness of the substrate. Each of these parameters may be used to modify other segments of the system 10 to assist with the treatment of a substrate 1.

[0046] An atmosphere control segment 200 is provided to assist with filtration or extraction of fluids from the system. During use the system 10 may be supplied with a dispersion, a primer, a bonding fluid, a monomer, a working gas and other fluids which may be desired to be removed before entering into the space outside the system 10. As such, atmosphere control segments 200 may be provided at the start and at the end of the treatment segments for the substrate. These segments may be used to restrict the movement of fluids from the system 10 with an air-lock 210 type device, and / or may also be fitted with extraction systems 215 which can be used to extract fluids as they pass a threshold of the system 10.

[0047] In another embodiment, the system may be designed without an air-lock, but instead may include a thin elongate gap defined by a top plate and a bottom plate which extend for 10mm to 1000mm in length in the direction of the warp of the substrate being processed. It is preferred that the top and bottom plates project relatively towards the unwinder of the system 10. Optionally, a portion of the plates may also project into an adjacent segment of the system 10. The top and bottom plates form said thin elongate gap through which the substrate 1 may extend and thereby restrict escape of fluids from thesystem 10. A lip may be provided which may interfere with the substrate 1 to be treated such that the lip formed a partial seal with the substrate 1. The sides of the top and bottom plates may be connected for stability and to reduce the potential for fluids to escape out of the sides of said plates. Optionally, a plurality of lips may be used to form multiple seals between the substrate and a plate. Lips may be situated on the top and / or the bottom plates. If more than one lip is provided, the lips may be angled towards the direction of movement so as not to impart a higher than necessary tension to the substrate 1. The front and rear atmosphere control segments may be adapted to fully house respective top and bottom plates, and these may form the atmosphere control desired for the system. It will be understood that the system can be adapted to operate at a higher pressure, between 0.5Pa to 2kPa relative higher pressure, than the atmosphere local the system such that system fluids are urged towards the gaps and external atmosphere is not sucked or siphoned into the system 10.

[0048] The gap between the two plates may be designed such that the fabric takes up at least a 5% volume of the volume bound between the top and bottom plates. Larger volume consumption of the volume between the plates may be desirable as this may further reduce the potential for fluids to escape from the gap. For example, a volume may be consumed by the presence of a substrate fed through between the plates, and thereby reduce the volume through which fluids form the system may escape. An entrainment of fluids may also take place wherein the speed of the substrate may also carry back into the system fluids which are in between the plates.

[0049] At the end of the plates, furthest from the processing segments, an extraction system may be positioned, which can collect fluids which escape from the plates. This extraction system may collect local atmosphere as well as the fluids from between the plates. Each of the entry and the exit atmosphere control segments may be configured to include an extraction system for removal of the fluids which escape from the plates.

[0050] Extraction systems 215 can be used to extract fluids which can be passed through a filter or a separation unit (not shown) which can solidify or condense materials which are desired to be collected or removed before venting into local atmosphere. Separation unitsmay be a cold-trap type device which can freeze out contaminants or may be used to solidify materials and direct them to waste vessels.

[0051] Optionally, the atmosphere control segment 200 may be integral to a subsequent segment of the system, such as the application segment 300 and / or the plasma segment 500. The atmosphere control segment 200 in these cases will form part of the other segment and function more similar to a module installed in said segment. As such, any reference to an atmosphere control segment may be interchanged with an atmosphere control module which will function in a similar manner but may be limited to extraction functions rather than an air-lock type control 210.

[0052] After passing from the atmosphere control segment 200, may be passed into a priming segment (not shown). The priming segment may be used to sterilise or clean the substrate before further processing. Priming segments may include one or more of the following devices: an autoclave, a steaming device, a spectral exposure device, a vacuuming system, an abrasion device, a padder, a spray applicator and a primer applicator. In another embodiment, a plasma segment 500 may be used as a primer segment in which the plasma segment 500 can be used to pre-treat a fabric or otherwise activate a surface of the substrate. This may include exposing the substrate to a predetermined plasma, and may optionally include the application of a plasma primer coating which may be similar to that applied as a fixation coating. Such coatings applied by a plasma segment 500 are discussed herein.

[0053] An autoclave can be used to reduce the potential for bio-organisms to survive on the substrate before processing and may eliminate odours or homogenise the substrate before reaching application segment 300. Steaming devices may be similar to autoclave devices in that they may be used to remove bio-organisms from the substrate, however the steam may also be used to wet or increase the moisture content of the substrate which may assist with fluid movement after application of a colourant or dispersion in the application segment 300.

[0054] Spectral exposure devices can use used for exposing the substrate to one of more sources of spectral emissions. This may include exposure to infrared light, ultraviolet light or other wavelengths which could be used to modify a surface texture or be used to reduce bio-organisms on the substrate. These spectral devices may be orientated such that the capture points are directed towards the face of the substrate.

[0055] Vacuum systems may be used to remove particulate matter or contaminants from the surface of the substrate before treatment. This is of particular advantage as particulates or contaminants residing on the substrate before treatment may interfere with the consistency of the coloured substrate after treatment. While vacuuming of the substrate may impart a pressure differential in the priming segment, the priming segment atmospheric conditions are not intended to impart any pressure reduction within the plasma segments 500 down the line.

[0056] In yet another embodiment, abrasion devices may also be used within a priming segment which can roughen the surface or physically modify the surface of the substrate which would increase or wettability of the surface or influence fluid movement of dispersion in the application segment 300. Abrasion devices may employ bristles or other rubbing elements which are intended to break fibres, roughen a surface, scratch a surface, etch a surface, or otherwise texture the surface before a dispersion is added to the substrate 1. Bristles or rubbing elements may optionally be actuated such that patterns or textures can be imparted to the substrate.

[0057] In a further embodiment, anti-pilling devices may be used to remove material which projects from a surface of the substrate. Removing material from the surface may assist with providing a more linear surface for application of a dispersion or pigment. Material removed may be extracted to a receptacle for collection. An anti-pilling device may include one or more blades which can cut or shear excess material from the substrate above a predetermined height or which exceeds a predetermined thickness.

[0058] A primer applicator may also be used, wherein a primer later can be applied to the substrate. Primer layers may be used as a backing or clean surface to which the dispersioncan be easily applied. A white primer layer may be desired to improve the vibrancy of a colourant applied with the dispersion in the application segment 300. Primers may be applied to the substrate as a thin film or a coating. The primer can be a polymeric primer which may improve the distribution of a dispersion applied in the application segment 300, or may be a degradable or removable primer which is used during processing and removed after treatment or is removed during a removal, cleaning or washing step. Primers may be used to reduce penetration of working gases or chemistries supplied during the plasma exposure step in segment 500. Optionally, the primer causes a reaction with a dispersion applied before being subjected to a plasma treatment in segments 500. Reactions between the primer and dispersion may improve the adhesion of the dispersion. The primer may be adapted to form a bond with the dispersing agent on the pigment after drying in a heating segment.

[0059] Any number or combination of primer segments can be disposed within the system. Primer segments may also be used to apply primers to a side of the substrate which it not to be treated by the application segment 300 and may be used to temporarily alter the properties of the substrate for the treatment process. For example, a disposable or removable backing may be applied with a primer segment which reduces penetration of the dispersion through the substrate. This may be of advantage if the dispersion is to be retained substantially on one side of the substrate. Further, it may be advantageous to apply a primer which may direct or temporarily fix pigments in a desired array, desired pattern or desired application distribution.

[0060] A primer may preferably be inert if being introduced to a plasma region, such that polymerisation or curing does not occur unless it is intended to do so. Primer layers may change at least one property of the substrate which may be; surface roughness, surface energy, porosity, or the material at the exposure surface to be treated. Further, to improve the spread of a dispersion across the surface of a substrate, the substrate may be applied with a functional treatment, such as a plasma treatment to at least temporarily make said substrate surface hydrophilic. Conversely, a hydrophobic or surface sealing coating ortreatment may be applied with a plasma module to reduce the adsorption of a dispersion into the substrate.

[0061] An exposure surface can be referred to as the treatment, which is the surface of the substrate to be applied with dispersion and / or exposed to a plasma. The exposure surface may be the surface which is desired to be coloured by a colourant and / or have a functional finish applied thereto.

[0062] While the system 10 illustrated includes only one side treatment processing, the system may include application devices for primer segments and application segments 300 which are adapted to treat both sides of a substrate. Alternatively, passing the substrate through the system 10 a second time to expose the other surface of the substrate may also be used to achieve a similar substrate with two sides treated. Treating substrate sides separately may be of particular advantage when applying different colourant dispersions to the substrate such that each side is a different colour, or may be of advantage when applying different functional finishes. Applying different functional finished may be used for applications such as durable water repellency (DWR), self-cleaning properties, anti- bacterial properties, anti-microbial properties, hydrophilic properties, and flame retardant properties. One or more of these properties may be isolated to a single side of the substrate or may be applied to both sides of the substrate.

[0063] DWR treatments may commonly be referred to as hydrophobic properties, and achieve a similar or the same effect as hydrophobic coatings. Chemistries to apply a DWR treatment may ideally be fluorocarbon free chemistries. Oleophobic coatings may be applied by the system which may be a coating which is also a water repellent coating.

[0064] Following the web handling entry apparatus 100, or the primer segment(s) if included in the system, the substrate enters into the application segment 300. Application segment 300 comprises a dispersion application device 310 which can be used to apply a dispersion to the substrate 1. The dispersion may be any dispersion pre-selected for application to the substrate 1, however in at least one embodiment it may be preferred that the dispersion comprises a colourant which can be used to colour a substrate 1. Thesubstrate to be coloured 1 can be any predetermined substrate 1. In at least one embodiment, the colourant may be a pigment which can be used to impart a colour to the substrate 1.

[0065] In yet another embodiment, the dispersion application device 310 is instead a pigment or powder application device which may be used to apply a pigment to a surface of the substrate without the need for a solution or dispersion to be present at the time of application. Electrostatic means may be used to evenly distribute pigments across the target surface of a substrate 1. Application methods such as this may be similar to that of a powder coating device, wherein at least one of a plate behind the substrate is charged or grounded to attract pigments which have been applied with a charge opposite to that of said charged or grounded plate. Alternatively, the substrate may be supplied with a desired charge to allow for attraction of the pigments.

[0066] In yet a further embodiment, application segment 300 can be used for applying a dispersion or pigment to a textile. The textile may be any textile composed of natural or synthetic fibres or yarns, which are woven, knitted, crocheted, or bonded together to form a fabric. The system may be adapted to process any type of textile including natural, synthetic or a blend thereof.

[0067] Common textiles which may be processed with at least one embodiment of the system 10 may be selected from the following; cotton, wool, polyester (and blends thereof), nylon, silk, acrylic, linen, rayon, velvet, denim, spandex, polypropylene (PP), polyethylene, Polytetrafluoroethylene (PFTE), and non-wovens.

[0068] The segment 300 may optionally be fitted with a primer module 315 which may be similar in function as the primer applicator discussed above. The application segment 300 further includes or is in communication with a reservoir 320 which can hold the dispersion to be supplied to the substrate. A reservoir may also be supplied within the segment 300 which holds a primer fluid which is in fluid communication with the primer module 315. The system 10 may be adapted to operate with dispersions with viscosity in the range of 1-200cPoise.

[0069] The primer module 315 may optionally include one or more printer heads through which a primer may be jetted onto the substrate 1. In this way the primer can be more evenly applied relative to spray techniques however some spray techniques will also allow for a general uniform or even application of primer. Knife coding techniques or other conventional padding techniques may also be used to apply the primer if desired.

[0070] Multiple reservoirs may be used to hold a number of dispersions which can be used to apply a desired dispersion or plurality of dispersions to the substrate. Dispersion application device 310 may be connected to a controller which may provide correct dosing of at least one of the dispersion and the pigment to be provided to the substrate.

[0071] Dosing of the pigment may be premade before the dispersion is provided to the system, or may be on-demand before the substrate is provided with the dispersion. On- demand pigment application may be useful for providing one or more loadings to a substrate, where a loading is the application of a desired volume of pigment. On-demand pigment may be advantageous if the pigment is difficult to disperse or a selective function is desired to be imparted to the coating provided to the substrate.

[0072] Conventional vibration pumps, recirculation pumps or sonicators may be in use before and / or during the application of the dispersion such that the dispersion be agitated before being applied to the substrate. This may allow for an improved dispersion of pigments within the dispersion which may result in a more desired and even coverage of the substrate being coated with the dispersion.

[0073] The application segment 300 with a dispersion application device 310 is used to apply a dispersion to a substrate surface. Dispersion device 310 is preferably housed within an application module, which can be used to reduce overspray or undesired application of dispersion. The dispersion preferably includes at least one of; a colourant, and a pigment. The pigment and the colourant may be one in the same. For example, an inorganic or organic pigment may be used as a colourant for a surface. Alternatively, an ink or other colourant may be within the dispersion and used as a colourant. Optionally, other pigments may also be included within a dispersion which may impart one or morefunctional properties to the substrate. For example, a TiO2pigment may be included within the dispersion and may be used to impart self-cleaning, stain removing, UV absorbing or oxidising properties to the surface of a substrate. Other pigments may also be used to impart other properties or colourants to the surface of the substrate.

[0074] A number of different application devices 310 may be suitable for use within the system 10. These devices may include at least one of; an air atomisation device, a hydraulic spray device, a pulse width modulation (PWM) device, an electrostatic spray device, or a fabric printing device may be used. Other devices may also be used which are common within the industry for applying a chemistry or dispersion to a substrate 1.

[0075] Spray techniques may be suitable for painting, coating, and surface finishing. The dispersion may have one or more colourants within, and may be used to impart a desired colour or shade to a substrate surface. These techniques may be carried out with the air atomisation device, hydraulic spray device, (PWM) device, and the electrostatic spray device mentioned above.

[0076] Air atomisation devices may be used with compressed air or other desired compressed gases, such as argon, to atomise liquid into fine droplets. The liquid is typically fed into the device and as it passes through the nozzle, high-velocity gas surrounds and breaks it up into a mist or spray. Air atomisation may produce finer and more uniform droplets, which can result in a smoother finish relative to hydraulic spraying devices. The control over the spray pattern and droplet size is usually more precise due to the ability to adjust the airflow and liquid flow separately.

[0077] Compressed air (or other gas) can be supplied to the atomisation device which can be used to create the spray from the atomisation device. The pressure of the gas can dictate the velocity of the colourant to be applied to the surface of the substrate. atomisation devices are suitable for both solvent-based and water-based coatings. Air atomisation may be preferred as a colourant option as these systems may provide for a better control for overspray relative to hydraulic systems.

[0078] Referring now to hydraulic spray devices, these devices require the use of hydraulic pressure to function. The hydraulic pressure can be used to urge the dispersion with a colourant through the hydraulic nozzle. The pressure of the dispersion causes atomisation into droplets as it exits the nozzle.

[0079] Hydraulic spray devices can produce a wider range of droplet sizes depending on the pressure and viscosity of the liquid. However, they may not achieve the same level of fine atomisation as air atomisation, particularly with low-viscosity liquids. A hydraulic pump or other pressure apparatus is used to urge the liquid through the nozzle. The pressure requirements can vary depending on the viscosity of the liquid being sprayed. Hydraulic spray devices may be desired for higher throughputs of substrate or where thicker dispersion applications are required.

[0080] It will be appreciated that the system may utilise a combination of any colourant application devices as discussed herein. For example, the system may use hydraulic spray devices to apply a primer layer to the substrate and the air atomisation spray devices may be used after to apply a controlled dispersion application.

[0081] A heating segment 400 may be positioned after the application segment 300, in which the substrate can be heated to a desired temperature. Heating the substrate may allow for moisture on and / or in the substrate to be removed before a fixation coating is applied. Conventional infrared heating lamps or ceramic heat emitters may be desirable for use within the system as these devices may allow for a generally rapid response in terms of removing moisture from the substrate 1.

[0082] A plurality of heating modules may be within the heating segment 400. Each of the heating modules may be adapted to heat the substrate to a different temperature such that a graduated heating can occur to avoid a rapid outgassing effect on the substrate which may cause pigment applied in the application segment 300 to move or appear uneven.

[0083] In another embodiment, the heating segment 400 comprises heating modules 410 with heating elements 415. The heating element may be an infrared heating element whichmay have a filament temperature of between 1300ºC to 1800ºC. The voltage supplied to the heating element may be around 1.5V to 5V per cm of heating element length. Reflectors may be used to direct heat to the substrate to be heated. Reflectors may be made of a radiant barrier material, or a reflective metal such as gold, aluminium, or silver. Other reflecting materials may also be used, but are preferred to be corrosion resistant.

[0084] The infrared heating elements may be short wave heating elements which may have an upper heating temperature of 2200ºC, fast response medium wave heating elements with an upper heating temperature of 1600ºC, or medium wave heating elements with an upper heating temperature of 900ºC. Each of these heating elements may have emissions of wavelengths in the range of around 0µm to 5µm.

[0085] A heating extraction 420 may be associated with the heating segment 400 which is adapted to remove water vapour, VOCs, or other evaporated or vapour fluids within the chamber. A filtration system may be used with the extraction system for removing the extracted fluids. Optionally, a chiller may be used to allow for condensing fluids extracted such that the fluids can be removed for further processing if needed, or chemicals extracted can be removed safely or removed for reuse.

[0086] Plasma segments 500 are positioned after the application segment 300, or the heating segment 400 if present. One or more plasma segment may be provided which are adapted to allow for a predetermined exposure of the substrates to a plasma region. The plasma region may include an optional monomer or precursor which can be used to form a coating or a film onto the substrate there by fixing the pigments or colourant to said substrate. Optionally the plasma may be used to polymerise or cure residual chemistries from the dispersion or a primer which has been applied to the substrate one in advance of entering into the plasma region. For example, humectants may be a residual component on the substrate which can be polymerised by exposure to plasma, and may therefore be used to fix colourant to the substrate 1.

[0087] Referring to Figure 2, there is shown an entry apparatus 100 of the system 10 which comprises an unwinder 115 for unwinding the substrate 1. The unwinder may bealternatively any receptacle or undriven device which has a substrate 1 within to be treated. A tensioner may be used to tension the substrate 1 at a desired tension for transport through the system, 10. The tensioner 130 may be a conventional device as known within the industry. An airlock 210 device may optionally be provided within the system which can be used to retain fluids within the system and reduce the potential for fluids to escape the segments of the system. The airlock device may be a pair of rollers in compression against the substrate 1. In another embodiment the airlock 210 may be a rigid surface and a pliable roller which compresses the substrate 1 there between. The compression of the substrate may be such that a desired tension is imparted to said substrate 1. The tension of the substrate may be in the range of 4N / cm to 130N / cm for textile materials. The pressure applied can be determined by using the tension force (N / cm) / substrate width (cm) to determine the pressure (N / cm²).

[0088] While different segments of the system may be optionally imparted with a different web handling tension, the system is preferably adapted to provide for a consistent or near consistent tension on the substrate 1 throughout the segments to reduce the potential for accumulation of the substrate.

[0089] Rollers may be used at intermittent spacings or predetermined spacing throughout the system to allow for the correct tension and web-handling of the substrate. It is preferred that the substrate is generally free from creases between the edges or selvedge (selvage) of the substrate when being transported through the system.

[0090] Screw rollers may be used as desired intervals which can be used to smoothen the substrate or generally remove wrinkles during transport and treatment of the substrate. This may be of particular use as the path of the substrate may be restricted in different segments, such as the plasma segment where the path of travel for the substrate may be in the range of 1mm to 10mm in height.

[0091] In another embodiment, a belt may be used to transport the substrate. The belt may move in the warp direction of the system towards the exit of the system when in use, such that the substrate is conveyed towards the treatment segments of the system 10. Abelt selected for this application may be porous or comprise one or more apertures which may allow for a dispersion to be applied and excess fluids may be removed readily. Further, apertures or pores of the belt may allow for a suction to take place which may draw the substrate towards the belt and assist with transport through the system. Optionally, an adhesive may be applied to the surface of the belt to temporally secure the substrate in place relative to the belt to assist with transporting through the system. The general locations of a belt, or belts, of the system may be generally below an application device.

[0092] Optionally, some segments of the system may be used to apply or extract fluids such that the fluids in the segments can be controlled or managed. Some segments, such as the heating segment, may have a volume of evaporated moisture which is to be transported from the system, or collected. The system may be adapted to capture and recycle the moisture collected from the heating segment when drying the substrate 1.

[0093] Some segments of the system may be fitted with active extraction which balances with the inputs of individual segments or a plurality of segments. Extraction of fluids may include extraction of gases and / or extraction of vapour.

[0094] Figure 3, there is shown an embodiment of an exit 110 of the system 10. The exit may comprise a rewinder which rewinds the substrate 1 onto a desired axis. In other embodiments, the substrate is pulled through and piled or laid in a receptacle for transport to any further treatment. The exit may have an airlock type device to reduce the potential for fluids to escape the system 10, similar to the airlock which may optionally be present at the entry of the system as described above. With an airlock the pressure within the system may be higher than that of the atmosphere relatively outside of the system segments. This may be of benefit as fluids may be urged towards lower pressure environments or urged out of extraction systems of the system while retaining a relatively controlled internal atmosphere.

[0095] The embodiment of Figure 3 may be generally the opposite of Figure 2, wherein the substrate will pass through an atmosphere control segment and then into a tensioner before being rewound onto a rewinder.

[0096] Figure 4 illustrates an embodiment of an application segment 300 which may be used to apply a dispersion and / or a pigment to the substrate 1. Optionally, a primer may also be applied within the application segment 300. A plurality of application modules 305 may be housed within the segment 300 which apply a dispersion or a pigment to a substrate. While a dispersion may have a pigment within, the application of a pigment is intended to mean a pigment which is not within a dispersion. Reference will be made herein to application of a dispersion, but optionally any such reference may be interchanged with the term “pigment” and mean a pigment which is not within a dispersion.

[0097] A dispersion application device 310 is fitted within a module 305 of the segment 300. The dispersion application device may be selected from any group of different dispersion devices discussed herein. Dispersion devices 310 may be mounted as fixed devices 310 in the modules 305 and provide a continuous or selective treatment for a substrate 1. Dispersion devices may be evenly spaced along the treatment width of the substrate and there may be one or more arrays of treatment modules provided within the segment as pictured. While four application module 305 rows are provided within Figures 1 and 4 illustrated, there may optionally be one row or any number of rows within a segment 300. Each row may be adapted to apply a unique dispersion, or select rows may provide a different dispersion relative to other rows within the segment 300. Optionally, each row may be used to apply a different dispersion comprising a different pigment type. This may allow for conventional CMYK colour applications, heptachromatography, or RGB type applications. Other conventional colouring methods may also be used with the dispersion devices 310.

[0098] In another embodiment, the dispersion devices 310 are adapted to move along a guide rail or are adapted to actuate in a predetermined manner such that application of a dispersion can be controlled and applied in patterns, arrays or as an even or graduatedblocked method. If the dispersion devices are adapted to move, a fluid conduit in communication with a reservoir will be adapted to also move with the dispersion device such that fluids from the reservoir can be provided to the dispersion device 310. Each dispersion device may have one or more heads from which a fluid can be provided to the substrate 1.

[0099] A heating segment 400 is positioned after the application segment 300 which can be used to remove moisture from the substrate being treated. The moisture may be the natural moisture content of the fabric, or may be moisture from ambient conditions outside of the system, or may be moisture from the dispersion.

[0100] Polymerisation, curing, or fixation is performed within the system by the plasma segment(s) 500. Pigments or colourants applied to the substrate are to be fixed to the substrate with a fixation plasma coating which is formed a plasma polymerisation of one or more of a precursor, monomer or chemistry which is supplied during the plasma process.

[0101] The dispersion applied to the substrate 1 by the dispersion application device 310 of application module 305 may be partially removed by the heating segment 400. It may be preferred that the dispersants, stabilisers and additives are removed from the substrate before a fixation plasma coating is applied to the substrate.

[0102] In a further embodiment, the substrate is provided with a dry pigment or powder by the powder application devices 311, and the heating segment 400 is optionally used to remove moisture from the substrate before a fixation plasma coating is applied by the plasma segment 500.

[0103] Turning to Figure 5 there is shown an embodiment of a plurality of plasma segments 500. Each plasma segment is adapted to generate a plasma with the use of plasma modules 510. Plasma segments 500 comprise a segment upper 501 and a segment lower 502. Segment upper may house a plasma module 510 or a portion thereof. The segment lower 502 may house a portion of the module or a plasma module 510 which corresponds to the plasma module 510 in the upper 501. A plasma module comprises atleast one pair of electrodes which are adapted to be charged to generate a plasma therebetween.

[0104] In yet another embodiment, the plasma module comprises two elongate dielectrics which are positioned to be respectively parallel, as can be seen illustrated in Figure 6. A metal conductor 525 is positioned on one side of the dielectric materials. Collectively the metal conductor 525 and the dielectric for an electrode 515. The dielectric material may have a surface area larger than the metal conductor 525. The metal conductor 525 may be any desired material, which can receive an electric current for use as an electrode. For example, the metal may be a copper, aluminium, steel, gold, silver, brass, or alloys of the aforementioned. The metal of the electrodes can be charged and a dielectric barrier discharge can be affected between the dielectrics. The space between the dielectrics of the electrodes is referred to herein as the reaction gap. Within the reaction gap a chemistry can be supplied which can be polymerised. A chemistry may be a monomer, a precursor, or any other polymeric chain which can be broken by plasma and recombined to make a coating or a film on a substrate.

[0105] A manifold 530 of the module may be used to supply a working gas the reaction gap and a monomer which can be polymerised. The plasma module is adapted to generate a plasma in atmospheric conditions. Atmospheric conditions may be at local atmospheric pressures in the range of 95kPa to 105kPa. The manifold is connected to a distribution system of the segment 500, and the distribution system is adapted to supply a ratio of chemistry and working gas to the reaction gap.

[0106] A power supply 600 may be used to provide a desired voltage, current, and desired power to at least one of the electrodes of the plasma module 510. Figure 7 illustrates an embodiment of a plasma segment 500 with a power supply 600 and cooling pumps 610 and a cooling reservoir 620 housed under the plasma modules 510 in the lower portion of the segment 500. A frame 20 defines footprint of the segment and provides a rigid structure in which the treatment systems and devices can be mounted. Each segment of the system may be fitted with a respective frame 20. The plasma module 510 can be configured which that there is an active and a ground electrode, such that the active andground electrodes form an electrode pair. Each electrode pair of the system may be adapted to operate with a discrete or predetermined voltage and / or power. In this way each module may generate a different type of coating, or a build-up of coating which may be formed from different laminations.

[0107] Different gases and / or chemistry may also be supplied to different modules 510 of the plasma segment. Different gases and / or chemistry may be used to form different coating layers and / or treat the substrate, or applied over pigments or coated substrate to modify the surface. Examples of gases which may be used may include argon, nitrogen or oxygen, which may generate a plasma to treat the substrate and pigments prior to a PECVD / plasma coating to improve adhesion. In some embodiments, argon or oxygen containing plasma may be used to treat a coated substrate to make it hydrophilic or hydrophobic.

[0108] In one embodiment, the system is adapted to supply generally the same voltage, power, and current to the plasma modules of the segments 500. It will be appreciated that minor voltage, power and current differences may occur and ±10% changes in a voltage, current and / or power supplied to adjacent plasma modules may be considered to be essentially the same.

[0109] The power supply 600 may be housed below the modules 510 of the segments 500. Each power supply may be used to provide a DC supply to one or more modules. Each module may optionally be fitted with a single power supply, or a single power supplies may be used to power a plurality of modules 510.

[0110] It is preferred that during use the modules 510 are supplied with a coolant or are actively cooled. A coolant may be passed through the metal conductor of the electrodes, or alternatively a heat sink may be fixed to the metal conductor which can be used to reduce or maintain a desired temperature range of the metal conductor. The desired operational temperature of the dielectric and / or the metal conductor during use may be in the range of 0ºC to 60ºC for a desired coating to be applied. As such, the cooling of the dielectrics and / or the metal conductor is desired, which may be affected with electrode cooling 540, toachieve the desired temperature range of 0ºC to 60ºC. Temperature of the dielectrics during the plasma polymerisation process may impact at least one of a coating thickness and the type of polymerisation of the chemistry provided to the reaction gap. A coolant reservoir may be in fluid communication with the electrodes or the heat sink such that the coolant can transfer heat from the electrodes 515.

[0111] Optionally, the reaction gap may be altered by moving the electrodes of the respective electrode pairs up or down relative to each other. It will be appreciated that other electrode orientations may be used in systems not illustrated, and therefore the reaction gap may be changed such that the electrode pairs are moved relative to each other away from a central plane which defines the middle of the reaction gap. It may be desirable that the electrode pairs are generally parallel to each other and aligned such that the centrelines of the electrodes generally correspond.

[0112] In a further embodiment, the sides of the dielectric material exposed to the reaction gap may be planar such that the reaction gap is bound between two planar surfaces. In this way a consistent electrode gap can be provided for the plasma segments 500. The reaction gap may be desired to be between 0.5 mm to 10mm such that the substrate can be treated without undesired electrical discharges during processing. It may be preferred that the reaction gap is between 1mm to 4mm during treatment of substrates with a thickness of between 0.01mm to 3.5mm thick.

[0113] Setting a reaction gap may be dependent on the desired coating to be formed during the plasma polymerisation process and / or the thickness of the substrate to be treated. It may be preferred that the reaction gap is generally not greater than around 2mm larger than the thickness of the substrate to be treated. Relatively thinner reaction gaps may be desired to reduce the power consumption of the system during use.

[0114] After a coating or film has been deposited onto the substrate 1, the substrate exists the segment 500 via an atmosphere control segment 200, and then is provided to the web handling exit 110. The web handling exit may comprise an air-lock type system or a similar fluid control system as the entry apparatus 100. A tensioner 130 may be providedand a rewinder 120 such that the desired tension is imparted to the substrate 1 while passing over rollers 125 before being rewound onto the rewinder 120.

[0115] Optionally, tensioning devices may be placed throughout the system and may be optionally housed in any segment mentioned herein. In a further embodiment, the tensioning devices may be mounted between segments and the seal between segments is facilitated by the tensioning portions.

[0116] To mount the substrate 1 for treatment, the substrate may be passed through a gap of the system. Said gap may be increased or decreased via a computer associated with the system. The computer may be associated with a human machine interface (HMI), or a remote system which can be directed to open or close the system for maintenance or processing. Each segment may have a processing gap independent of adjacent segments. For example, the processing gap in a plasma segment may be the reaction gap, which when in processing is generally between 1mm to 4mm (although larger gap sizes are also envisioned as described before). As a processing gap of 1mm to 4mm is relatively small for a web to be mounted, the processing gap may be expanded to allow for mounting of the substrate 1 therebetween. In this way, the upper 501 and the lower 502 may be separated to provide a gap large enough to easily mount the substrate to be processed. In other segments similar upper and lower segment sections may be provided which may assist with mounting of the substrate and / or maintenance. It may be desirable to have a processing gap through which modules or components of segments can be removed.

[0117] Colouration and Dispersion

[0118] The application segment 300 of the system may be used to provide a dispersion to the substrate 1 in a desired manner. Preferably, the dispersion applied to the substrate can be controlled such as not to saturate or over-wet the substrate during processing, which may make web-handling relatively more challenging.

[0119] Colour may be applied to the surface of a substrate with conventional methods such as printing, digital printing, electrostatic application, atomisation, hydraulic spraying,and nebulisation. Colour may be in the form of a pigment, pigment dispersion and / or a dye. These methods may also include other suitable methods known within the art for application of a pigment and / or a liquid in a desired manner to a substrate surface. Pigments are ordinarily insoluble in water and some other organic solvents. These types of pigments are generally desirable for water based dispersions and ink dispersion formulations. A solvent which may be suitable for the present dispersions may be water, deionised water, and / or distilled water.

[0120] For a successful pigment dispersion additives may be used to assist disperse and stabilise pigment particles while also preventing or reducing agglomeration through various chemical interactions, including van der Waals forces, "liquid bridge" forces, and anchor groups that strongly adhere to the pigment surface. Wetting agents may be one additive which can be used to assist with spread of the dispersion across the surface of a substrate and may allow for a more even coating to be applied. Anchoring groups may provide for strong adsorption onto the surface of a pigment, with the stabiliser added after the anchor groups have been introduced to the pigments. Anchor groups may instead be electrostatic charges imparted to a pigment. If an anchor group is a polymeric anchor group, the polymer may be a single anchor polymer, or a multiple anchor polymer. Dispersions may also be provided with one or more synergists which are pigment derivatives having strong affinity for certain pigments. These may be used to anchor to a pigment surface to provide a desired functionality and / or to enhance adsorption of a dispersing agent.

[0121] Additionally, the efficiency of the dispersion process greatly relies on the performance of dispersion equipment, including its energy transfer, dispersion force, and overall effectiveness. It may be found that the most advantageous dispersions are accomplished through shearing forces generated by applying intense positive and negative attrition.

[0122] Dispersions suitable for use with the system may generally have the desired end properties of good pigment distribution, fastness, opacity, storage stability, gloss and colour strength when using pigments for colouration purposes. It may be preferred that ifthe pigment to be applied to the substrate is for garments, the pigment may be organic as these types of pigments may provide a more desirable colour intensity relative to that of inorganic pigments. However, it will be appreciated that the opacity of inorganic pigments in some instances may be superior to that of organic pigments and be desirable for colouration applications.

[0123] Van der Waals and the “liquid bridge” forces may be the primary attractive forces which hold together pigment particles in the dry state. As such, to obtain successful dispersal of the pigment particles in liquid media these forces must be overcome. When the attractive forces are overcome, repulsion sets in and stability can be achieved. This is the preferred type of dispersion which may be used with the system of the present disclosure. The cohesion force that acts between pigments to cause agglomeration are generally physical in nature, but may also have a chemical bond in some situations. They are composed of van der Waals attraction, London and Coulumbic forces as well as hydrogen bonding.

[0124] Energy is required to distribute the pigment particles in a continuous liquid medium with the aim of pigment particles completely surrounded by said liquid medium and eliminate permanent pigment contact. To better assist with achieving this, the pigment dispersions may desirably have a medium adapted to keep pigments separated after initial separation processing. Wetting and viscosity of the pigments may play a role in achieving a desired stability and dispersion of the dispersion formulation. Pigment dispersions have small particles to assist with achieving high stability and reduce agglomeration.

[0125] To separate agglomerated pigments, pigment particles are broken down into a liquid medium and each pigment particle covered by said medium. In this way they may become uniformly distributed throughout the dispersion formulation. Of importance is the balance between an attractive van der waal and repulsive electrostatic force, to allow for pigment stability within the dispersion formulation. Separation of the agglomerated pigments or larger pigments may be achieved with mechanical separation methods such as smashing, impingement and shear methods. Other separation methods may also be used, such as ultrasonic separation.

[0126] After mechanical separation wetting process where components of the medium spread over the particle surface to replace the initial pigment / air or pigment / moisture interface by a new pigment / medium interface. It may consist of the solvent and binder, followed by mechanical destruction of the agglomerates. Complete wetting occurs when deflocculation and disagglomeration have both occurred. Deagglomeration may be achieved by the use of mechanical dispersing units with high shear forces which enhances interaction between individual particles causing them to solvate and thus wetting is achieved. This stage is very susceptible to new agglomerations and therefore it is important to stabilise as soon as practicable. Dispersion of the pigments may also be affected during milling, such that the milled pigments may not agglomerate or the potential for agglomeration is reduced.

[0127] Polyhedral Oligomeric Silsesquioxane (POSS) or Trisilanol POSS may be used as a dispersant in some dispersions. It will be appreciated that dispersing surfactants may also assists in pigment wetting, when an insoluble particulate inorganic pigment is been used surfactants wet very well in strong acidic and highly alkaline medium. Some other additives which may be desirable may include polyethylene glycol (PEG) for defoaming, and cetylbromide. The PEG may have a molar mass of around 670.

[0128] Other molecular weights of PEG may be used which can typically be in the range of 200 to 600, as a humectant and viscosity modifier. PEG may be used in combination with other additives to optimise at least one of; jetting performance, pigment stabilization, and substrate interaction. These additives may include polypropylene glycol to adjust hydrophobicity and drying behaviour, polyethylene oxide for rheology modification, and PEG derivatives such as monomethyl ethers, diacrylates, dimethacrylates, esters, and sorbitan esters to provide surface tension control, surfactancy, or reactive cross-linking capability. Additional water-soluble polymers such as polyvinylpyrrolidone, polyvinyl alcohol, and polyacrylic acid or its salts may be used to stabilise pigments and enhance film formation. Low-volatility humectants including propylene glycol, dipropylene glycol, sorbitol, and glycerol are incorporated to prevent clogging and control evaporation, while cationic polymers such as polyethyleneimine may be employed to promote pigmentbonding with the fibre. These additives may be selected individually for a predetermined application provide stable dispersions, desired droplet formation, controlled dispersion penetration, and apply a desired visual colouration to the substrate 1.

[0129] In some dispersion formulations, latex on surface structure of the pigment for wetting of pigment coatings may be desired for some substrate coatings, such as those which may be applied to paper and used within paints.

[0130] Binders may be acrylic binders which are alkali soluble. These types of binders may provide for a polymerizable film which may be flexible and have a solvent resistance. Such binders may be used for temporary protective coatings which may be of particular use for disposable or temporary products.

[0131] Styrene-acrylics can be used for producing a hard coating around a pigment, and may provide a level of gloss and allow for a high brightness of pigment. Styrene-acrylics may be suitable for cross-linking epoxy. A variety of other components are added to give a wide range of properties, and reinforce physical, mechanical and thermal properties. They may also be of low viscosity or high molecular mass solid resins. Styrene-acrylics may be used to form films if they are polymerised by the plasma process.

[0132] It will be appreciated that the dispersion applied to the substrate may be preferred to be free of as many binders as possible, such that during the heating process in the heating segment the majority of the dispersion can be evaporated.

[0133] In may be desirable to have some volatile components of the dispersion which may be readily removed from the substrate surface during the heating process. These volatiles may be alcohols, butanal, acetic acids, acetones, carbon disulfates, formaldehyde, methylene chloride or other VOCs which may be removed at least in part with heating processes. Optionally, the plasma process may be adapted to polymerise some of these volatiles and form a portion of a coating or film with the substrate.

[0134] In another embodiment, the dispersing agent surrounding the pigment may remain after drying. The dispersing agent may be used to form a hard shell around the pigment during the plasma process, whereby the dispersing agent may be polymerised in the plasma and a plasma coating applied over the polymerised dispersing agent on the pigment. The resultant coating from this process may be a pigment surrounded by a polymerised dispersing agent shell and a plasma coating provided over the top of the pigment and dispersing agent to bind the pigment to the surface of the substrate.

[0135] The dispersing agent around the pigment may be partially removed or evaporated during the drying process, which may leave portions of the pigment without a dispersing agent surrounding the pigment. In these cases, the plasma coating provided will be in direct contact with pigment and the dispersing agent. In some embodiments, the dispersing agent may remain, at least partially, around the pigment and the dispersing agent will not be polymerised within the plasma, but assist with forming a desired fixation bond between the pigment and the fixation plasma coating.

[0136] The heating process may be used to remove all, or substantially all, of the stabiliser and dispersant from the substrate before the substrate enters into the plasma segment 500. The remaining dispersion portions are preferably the pigment alone, however in some instances it may be desired that dispersing agent may also remain on the pigment to assist with improving a bond between the plasma coating and the pigment. Binders may also be used to assist with bonding between the plasma coating and the pigment. Other additives may also be used if they are residues which can be polymerised within the plasma region.

[0137] Covalent bonding between the pigment and the plasma coating may be present after treatment, or covalent bonding between the dispersing agent and / or the pigment and the plasma coating may occur after a plasma coating process.

[0138] It will be appreciated that any polymerisation on of a dispersion within the plasma of the plasma segments 500 will not be sufficient to form a coating, and a plasma fixation coating must be provided during the plasma process.

[0139] Dispersion application devices may be mounted in any predetermined configuration or array above the surface to be treated. If the dispersion application device is relatively close to the substrate to be treated, within 30mm, the dispersion application device may be orientated in any desired direction to face the substrate, which may be of particular use for printing head devices.

[0140] Other dispersion devices which reply on aerosols and spraying may require a larger spray pattern for even application of a dispersion, and therefore they may be mounted at a suitable distance which may be between 50mm to 600mm from the surface of the substrate.

[0141] In yet another embodiment, the pigments from the dispersion may be physically altered by the plasma process. A pigments after plasma exposure may have edges or sides smoothed relative to its appearance pre-plasma exposure. The plasma process may be used to etch or break down portions of the pigment and allow for rougher surfaces to be smoothed. In some cases, the plasma may be adapted to allow for smoothing of the top (between 10-50% of the surface area, or the general morphology of the pigment) of the pigment, and the remainder of the pigment is relatively unchanged before and after plasma exposure. Alternatively, greater than 75% of the pigment surface or the general morphology of the pigment may be altered during a plasma exposure. Breakdown of the pigments may also occur during the plasma exposure and may cause fracturing or splitting of the pigment into smaller pigment portions. This may be desirable as this may allow for a plasma coating to be applied more easily over the pigment portions as the pigment relative heights may be reduced relative to the surface of the substrate.

[0142] As a dispersing agent may be used to penetrate and / or cover the surface of the pigment, the dispersing agent may be polymerised by the plasma to smooth the surface of the pigment. In this way the polymerisation of the dispersing agent will physically alter the exterior of the pigment during the application of a fixation plasma coating in segment 500. The dispersing agent which smooths the edges of the pigment can be used to break down or break away portions of the pigment to create a smoother surface of the pigment. Agglomeration of pigments may also be broken down, and larger pigments may also bebroken down into smaller pigments. Breakdown of pigments may result in a surface topography with a similar roughness as the original pigment pre-breakdown, or may be imparted with a different or more desired surface topography which may be relatively rougher or smoother.

[0143] In yet a further embodiment, the dispersing agent may form a hard coating around the pigment and thereby fill in the undulations or rough surface of the pigment creating a smoother overall pigment surface. A polymerised coating on the pigment in this regard may be considered to form part of the pigment structure. This may be desired as the pigment size distribution can be fixed while also providing for a smoothing effect on the pigment. Smoother pigments may have a superior abrasion resistance.

[0144] In yet another embodiment, a portion of the dispersion remains as a residue which is polymerised to alter the shape of the pigment. The residue may be adapted to polymerise and fracture portions of the pigment during the polymerisation process. The residues may also for a chemical bond with the pigment during the polymerisation process. Polymerised materials can be used to form a portion of a bond between the substrate and the pigment. Residues may be any additive which has been introduced into the dispersion and may also include the dispersant and / or the stabiliser. Preferably a large volume of these products from the dispersion are removed before plasma exposure as the plasma may be energised to only polymerise thin residues on a substrate and the chemistry introduced into the reaction gap. Application of dispersion without an evaporation or fluid removal process may result in a partially polymerised coating which is insufficient to form a coating which may survive the intended purpose. For example, if the substrate is a textile for a garment, the coating formed by the plasma may be eroded or removed during a washing process, and thereby cause failure of the coating.

[0145] In some embodiments, a partial polymerisation process may be desired, which may allow for a release of ions or medicaments when the polymerised surface is abraded, scratched or heated. The unpolymerised portion of the coating below the polymerised portion of the coating may be allowed to flow, break or move the polymerised portion of the coating to move towards the exterior surface of the coating. In this way medicamentdelivery may be made over a windowed period with a delay in delivery until a heating step has been completed.

[0146] Smoother pigment surfaces may provide for an improved wet and / or dry rub fastness score relative to the same pigments without a smoothing process. The smoothing process may allow for abrasives to slip over the surface of the pigment more easily and thereby reduce the potential for damage to the pigment which may remove it from the fixation coating applied during the plasma process, or may cause portions of the pigment to be removed and thereby dull the overall appearance of the pigment.

[0147] It has been observed that exposing the pigment treated substrate to a plasma, which contains argon or oxygen, results in a significantly improved rub fastness relative to no plasma treatment, or a plasma treatment in the absence of argon or oxygen. Smoothing of the coated surface can be observed with this type of treatment. Furthermore, when an argon or oxygen containing plasma and monomer is applied, the smoothing effect is also observed. An increase in rub fastness and wash fastness may be achieved using this method.

[0148] Following the wetting process, the disruption process in which flocculates are broken down by high shear force, until the required degree of dispersion is attained. As the grinding equipment introduces mechanical energy in the system, shear force breaks and separates the pigment agglomerates in smaller particles. The liquid in the grinding medium then wets the newly created surface.

[0149] Dispersion stabilisation Uniform distribution and stabilisation are only achieved after disruption and wetting. Stabilisation of pigments in aqueous media requires special additives to reduces the remarkable high surface tension of water and also enables better wetting of pigment. Stabilisation of pigments may be achieved by either electrostatic stabilisation or steric stabilisation methods.

[0150] In some embodiments, it may be preferred that the pigments are dispersed with electrostatic stabilisation as charged particles may allow for a generally even distributionwhen applied to a substrate while also being less likely to require resins or polymers within the formulation, and electrostatic stabilisation may also be suitable for water-based dispersion formulations.

[0151] For plasma exposure, pigments may optionally be selected from complex inorganic colour pigments (CICPs) as these pigments may retain colour in plasma environments compared with some pigments which do not fall into the CICPs category. This colour retention may be due to the inertness of the pigments with exposure to UV and ozone, which may be present within the plasma reaction gap. Furthermore, CICPs may also be generally non-migratory and remain fixed in a desired location and be less susceptible to solvents.

[0152] CICPs may also be of particular use for UV scattering and therefore UV protection for a substrate. This may be of particular use for substrates which degrade rapidly within the natural environment, such as in outdoor conditions which may allow for utilisation within building materials or other geotextiles. Alternatively, this may also be of particular use within hospitals or lab environments in which UV lighting may be commonly present.

[0153] Additives include insulating additives, powder coating additives, catalysts, stabilisers, wetting agents, dispersing agents, thickeners, binders, levelers, clarifier, coupling agents, emulsifiers, deflocculants, thinners, thickeners, anti-caking agents and other chemicals. Dispersing agents may be used to prevent pigment agglomeration and both during milling and longtime storage. Dispersion agents aid stabilizing pigments via anchor groups with a high affinity for the pigment surface thus establishing repulsive forces between individual pigment particles.

[0154] Additives for a dispersion may include a solvent, a binder and additives. The dispersion may further comprise may be optionally present within the dispersion. The dispersion may also comprise a solvent which can be used to carry one or more additives within the dispersion and may be used to carry a pigment or colourant.

[0155] Thinner mediums may be added to the dispersions by the system based on the desired dispersion application to the substrate. These mediums may be used to dilute the pigment to dispersion ratio, such that there is more dispersion with the same volume of pigment within. This may be of use when a higher volume of solvent, binder, or additives are required compared to the pigment. The addition of thinner may allow for a more desired evenness of the pigment across the surface of the substrate to be treated.

[0156] Flow improvers may be used which may be similar to a surfactant. These additives may be used to reduce the surface tension of the dispersion and thereby reduce the chance of tide marks or pooling of pigment on the surface of the substrate 1. One or more flow improvers may be added to the dispersion, which may allow for improved distribution of the pigment across undulating or uneven surfaces. For example, flow improvers may be useful for dispersions applied to textile substrates, which may be woven or non-woven.

[0157] Drying retardant may be another additive which may be included within the dispersion. Drying retardants may be used to reduce the potential for tide marks, or pigment movement during the drying process in the heating segment 400.

[0158] In some embodiments, the dispersion may include a polyurethane such that there is a varnish type additive which may provide a level of durability to the pigments on the substrate.

[0159] While some additives may remain on the surface of the substrate after drying, the residual additives on the substrate are not used to bind the pigment in place, but rather the plasma segments of the system are adapted to provide a binder coating to retain pigments in place. Additives remaining on the substrate surface may be optionally polymerised within the plasma. To optionally polymerise additives within the plasma the first modules within the plasma segments may be adapted to only provide a working gas from the manifold such that the plasma generated is not supplying a new chemistry to be reacted along with the working gas. This may allow for residual additives on the substrate to be polymerised.

[0160] drying retardants may be used to reduce the potential for drying to occur before being introduced to the, or they may have flow improvers to allow for the pigments to be transported more evenly across the substrate surface. The transport of these dispersions may be along the fibres of the substrate when coating a textile, or may be along a primer surface if a primer surface is present. The application of the dispersion to a substrate with a relatively more consistent surface may allow for a more even distribution of dispersion across said surface.

[0161] The dispersion may comprise pigments which act as a colourant. The pigments may be provided to the substrate in a predetermined diameter or size. It may be preferred that the pigments are broken or otherwise are not in an agglomerated state at the time of application. Reducing the size of the pigments may be advantageous as this may allow for a reduced volume of colourant to be used to colour a substrate. Further, a reduction of pigment size may also assist with colourfastness of the coloured substrate. Larger particles may protrude above a fixative coating which bonds or otherwise holds in place the pigment with the substrate.

[0162] If pigments are larger than the coating surface they may be abraded or broken from the surface of the substrate. This configuration of coating may have application which respect to dispersions where the pigments are medicaments or ion diffusing materials. For example, antibacterial pigments may be used for bandages or other wound facing surfaces. Pigments in these embodiments may include silver, silver salts, silver oxides, TiO2, magnesium or zinc. Applications for medical devices are discussed later.

[0163] Turning back to colourant applications, the loading of pigment is preferrable as evenly distributed as possible for an even colour appearance. However, if uneven colours appearances are desired, darker regions may be made with higher pigment loading and lighter regions may be made with relatively lower pigment loading. Pigment loading volumes may change depending on the colour being applied and the opacity of the pigment.

[0164] The general range of pigment sizes may be in the range of 20nm to 400nm. Pigment sizes may also be within the range of 1nm to 1 micron. More than one pigment may be within a dispersion and each pigment type of the dispersion may be of a discrete size. For example, a black colourant pigment may be in the range of 50nm to 150nm, and a second blue colourant pigment may be in the range of 100nm to 200nm. Any other combination of colourant pigments and sizes of said colourant pigments may be used within a dispersion.

[0165] For colourant applications, the pigments may be preferred to be water insoluble such that they are not removed during washing processes, for example if the substrate is to be turned into a garment.

[0166] With respect to water soluble pigments, these may be used for tamper-evident products wherein the pigments may be exposed to water or other liquids and may have colour removed. This may also be or particular use for sanitary products which require fading images or decals.

[0167] Dispersions may have one or more additives to distribute or otherwise allow dispersion of the colourant or pigments. It is preferred that at the time of exposure to plasma, the additives are either inert, non-reactive or are otherwise removed from the surface of the substrate such that the fixation coating formed in the plasma is formed substantially by the monomer, chemistry and gases supplied to the substrate during plasma exposure. While the dispersion could utilise a reactive species which could be polymerised within the plasma, it is preferred that the fixation coating is applied at the time of plasma exposure.

[0168] One large benefit of removing reactive materials which may polymerise within the plasma is that the pigments are more likely to be situated at the surface of the substrate during plasma exposure. This may allow for an improved fixation of colour relative to methods which have a chemistry which may be polymerised within the plasma being part of the dispersion. Chemistries or monomers within a dispersion applied to a substrate maypolymerise relatively more slowly than chemistries or monomers which are supplied in an atomised, aerosolised or otherwise gaseous or droplet phase.

[0169] While the additives of the dispersion is not desired to be polymerised, the additives may be used to change the morphology of the pigment when exposed to plasma. Changing of the morphology of the pigment may improve colourfastness properties.

[0170] Any number of additives in a dispersion may be used, however it is preferred to minimise the number of additives such that they can be more easily removed before the substrate is exposed to plasma. Additives are primarily used to disperse the pigments across a surface of the substrate evenly while also allowing the pigments to stick to the substrate during a heating process.

[0171] Plasma may be used to modify pigment structure or their properties before being coated or fixed with the substrate. The modification may be used to assist with physical fixation by etching or breakdown of the pigment or substrate to form a structure which may more readily be adapted to fix the pigment with the substrate.

[0172] The properties of the coating applied during the plasma process may be such that the coating at least partially embeds the pigments in said coating on the surface of the substrate, or the pigments are fully or substantially (greater than 75% of pigments delivered) encapsulated within the coating. Encapsulation may be understood to be the covering of the pigment such that one side of the pigment is abutting or generally proximal the surface of the substrate and the other portions of the pigment are generally covered by the coating applied during plasma fixation.

[0173] It is preferred that the thickness of the coating, or the build-up of coating at the contact end of the particle, is sufficient to embed the particle or fix the particle in a desired position. The thickness of the coating thickness may extend at least 5% of the height of the particle. Preferably, the particle is encapsulated by the coating, or encapsulated between the substrate and the coating. Encapsulation means that the outer faces of the pigments are fully surrounded by the coating and / or the substrate.

[0174] To encapsulate a pigment the general range of pigment sizing expected may be used to determine the thickness of the coating. For example, if the size range of pigment is to be in the range of 50nm to 200nm, the thickness of the fixation coating may be in the range of 150nm to 300nm such that at least 50% of the size of the pigments deposited onto the substrate are within the fixation coating. It will be appreciated that some pigments may be agglomerated, larger, or otherwise stacked above the expected size range of the pigment and therefore may not be fixed in the same manner as pigments immediately adjacent the substrate which are not agglomerated, are within the expected size range, and / or are not on top of other pigments. The surface roughness and material construction or material type may be a factor when selecting parameters for dispersion application and / or plasma settings.

[0175] It will be appreciated that the longer the exposure to plasma in the system the thicker the final coating will be as the coating will continue to build in thickness during exposure with new supply of precursor or monomer.

[0176] The advantage of PECVD processing is that the precursor or monomer will form covalent bonding location with the pigment or colourant applied to the substrate and with the substrate. In direct contrast to conventional methods within the industry for applying functional finished or coatings to a textile, the conventional application methods do not form bonds readily with the fibres of the substrate or the colourant, but rather form shells or coatings which are not directly bonded with the fibre or colourant. Instead, the finishes or colourants are generally physically disposed within the fibres or the finishes form cured shells or coatings which bond with only the finishing chemistry rather than the underlying fibres.

[0177] It may be preferred that the finish for the substrate 1 applied by the plasma modules is relatively smooth such that abrasion is unlikely to chip, crack or break the coating formed. Further, with smoother coatings on the substrate there may be an improved colourfastness provided.

[0178] In at least one embodiment, it may be desirable to functionalise the fixation coating provided to the substrate such that the upper surface exposed to the environment after exiting the system is hydrophobic. Having a hydrophobic surface may reduce the potential for liquids to enter into the substrate and lift or otherwise separate the fixation coating and / or the colourant from the substrate 1.

[0179] If the substrate has a level of porosity, the plasma treatment process may allow for a portion of the treatment to pass through to the side which is not adapted to receive the coating produced from the plasma. Alternatively, the gas flow may be partially directed to allow a coating to be deposited to both the first and second sides of the substrate 1.

[0180] Depending on the porosity of the substrate the fixation step may allow for a coating to be applied on both sides of the substrate. Pores of the substrate may allow a portion of the coating formed by the plasma treatment process to permeate or penetrate through from the first side of the substrate to the second side of the substrate. For example, if the upper side of the substrate (a first side of the substrate) is to be treated, the plasma segments 500 may be adapted to supply a chemistry relatively above the upper side of the substrate for polymerisation and deposition onto the substrate.

[0181] Particle geometry and sizing may be desired to be selected from the general group of; plates, platelets, cubes, acicular (needle shaped), angular (sharp edged or having roughly polyhedral shape), crystalline (freely developed in a fluid medium of geometric shape), dendritic (branched crystalline shape), fibrous (regularly or irregularly thread like), flaky (plate like), granular (having approximately an equidimensional irregular shape, irregular (lacking any symmetry), modular (having rounded, irregular shape), and spherical (global shape). One or more of these shaped particles may be desired to be within the dispersion and may improve at least one of a wet-rub fastness score, and / or a dry-rub fastness score. These pigment shapes may be applied within the application segment 300, and may be modified in structure within the plasma segment 500, as is discussed herein.

[0182] In one embodiment, the particles may be desired to be more flaky such that they are able to be relatively more parallel with the surface of the substrate to be coated, thismay allow for a fixation coating to be applied more effectively and have a higher potential for the fixation coating to embed or encapsulate the flaky pigment structure. The more of the pigment covered or coated with a fixation coating, the higher the potential for retention at the surface of the substrate.

[0183] Similarly, spherical geometries of the pigments may also allow for an improved pigment fixation in relation to abrasion. The spherical geometries allow for a reduce catching during abrasion and therefore the pigment may have less chance of being dislodged from a fixation coating.

[0184] Application of the colourant may be 1-400mm from the surface of the substrate to be applied with colourant. Optionally, the colourant may be applied on the upper side and the underside of the substrate. The application of the colourant may be sequentially applied on a first side and then to a second side of the substrate, or may be applied simultaneously.

[0185] In yet a further embodiment, the colourant may be applied to a first side of the substrate, passed through the system to fix the colourant on the first side of the substrate. The substrate may then be passed through the system a second time such that the colourant can be applied and fixed to the second side of the substrate. Applying colourant in this method may allow for the first side of the substrate to receive a first colourant and the second side of the substrate to receive a second colourant.

[0186] Colour printing

[0187] System colour selection may be similar to conventional printing methods which may employ a monochrome to hexachrome colour method, or in some embodiments a heptachrome colour method may be used. Pigments, dyes, or other colourants may be used to provide each chromatic for the method used. Colourants may be applied in one or more application processes and individual pigment applicators may be used to provide distinct colours, or one or more pigment applicators may be used to provide one or more colourants as desired.

[0188] In another embodiment, pigments which are colour imparting pigments may be provided with a CMYK (cyan, magenta, yellow and black) colour array to a substrate. CMYK colouration of a substrate have use halftoning or screening which allows for less than full saturation of the primary colours. Using this method may use tiny dots of each primary colours printed in a predetermined manner which imparts a desired visual colourant.

[0189] The system 10 may be adapted to allow for a premixing of colourant pigments such that a desired colourant is formed for application to a substrate 1. In another embodiment, the incremental application of pigment may be desired, wherein a first pigment application module may be used to apply a fix pigment, or pigment mixture, to a substrate 1, and a second pigment applicator may be used to apply a second pigment or pigment mixture to the substrate thereafter. More than two pigment applicators may be used in this way, and each may be adapted to apply one or more predetermined pigments to the article. In this way a desired pigment can be imparted which may have a desired colourant from the application of multiple pigment colourants. In a further embodiment, a pigment applicator may be provided which corresponds to one of the colourants for a CMYK process, such that four pigment applicators are used in the process. Similarly, any number of pigment applicators may be provided with each applicator corresponding to a distinct colourant for a chromatic process, from a monochrome process to a heptachrome process. In addition to any number of applicators generally required for a predetermined chromatic process, the system 10 may further include a white pigment applicator in addition to any other pigment applicators. This is to say that for a heptachrome configuration, around eight pigment applicator 18 may be desired.

[0190] Colourants may be controlled by controlling loading rate of the pigment to a substrate, or may be controlled by the inclusion of white pigment colourants or lighter tone pigment colourants which may augment or change the intensity or overall visual colourants applied to the article. Each of the colourants applied to a substrate may be applied in a predetermined volume or by weight. The system controller 11 may be configured to dose correct volumes or loadings for a desired resultant colourant on the article.

[0191] In yet a further method, the system may also use spot colour printing wherein specific colourants are used to generate colours on a substrate 1. A spot colour or solid colour may be any colour generated by an ink, pigment, or other colourant, which may be pure or mixed, that is applied to a substrate in a single run, whereas a process colour is produced by printing or applying a series of dots of different colours to affect a desired colour which can be perceived by a viewer. Dots may be applied as pigments which may be printed, sprayed, or deposited onto the substrate 1. CMYKOG methods may utilise a similar colour array as that of CMYK, but further include orange and green colourants which can be used to provide a more defined and accurate colour relative to CMYK methods.

[0192] Optionally, Pantone™ colour systems may be used which is a six colour hexachrome system CMYKOG which may expand the gamut of the available colours greatly. However, it will be appreciated that other hexachrome methods may also be used, such as the CcMmYK colouration methods, which further include light magenta and light cyan colourants. Light, saturated colours often cannot be created with CMYK, and light colours in general may make visible the halftone pattern. Using a CcMmYK process, with the addition of light cyan and magenta inks to CMYK, can solve these problems.

[0193] While some examples of colour systems have been discussed, it will be appreciated that the system may be adapted to utilise one or more other standardised or common, colour systems within industry. For example, the system may be configured to use at least one of; Pantone™, Toyo™, DIC™ Colour System Guide, ANPA™, GCMI™, HKS™ (Hostmann-Steinberg Druckfarben, Kast, Ehinger Druckfarben and H. Schmincke & Co.), and RAL™.

[0194] RAL CLASSIC™ colour systems may be primarily used for powder coating colourants, and may have a desired classification method for a range of industries. It will be appreciated that as each system is designed independently, colours from a first colourant system may not be possible to form with a second colourant system. However, the system may be adapted to accommodate pigments or other colourants which can accommodate for more than one colourant system.

[0195] As pigments may be desired infrequently, or some pigments used less than other pigments, the system may have one or more devices which can agitate, mix, move, or sonicate the pigment before application to a substrate 1. This may allow for a more consistent final colourant to be applied to a substrate 1.

[0196] Pigments may be optically assessed for an average colour of a pigment and the system 10 may be adapted to dynamically adjust the final colourant by mixing ratios of pigments in a predetermined manner. Mixing these pigment colourants may be similar to conventional printing methods.

[0197] Similar to conventional laser printing devices, the pigment applicator may be adapted to add colourant in a predetermined manner to create a predetermined colour pattern or image. A plurality of toner and developer units may be mounted on a rotating shaft or wheel. In this manner the printer may then apply an electrostatic image for one colour and aligns the toner into the desired position. The colour may then be applied and the next colour required can be moved into position to repeat the process as needed.

[0198] Alternatively, all colourants may be added to a plate before transferring the image on the article. Some methods of applying pigments to the substrate may be limited based on the geometry, thickness, or topography of the article.

[0199] Natural pigments may be plant pigments chlorophylls, anthocyanins, carotenoids, and betalains. Natural pigments may also include biological pigments selected from the following group: Heme / porphyrin-based, chlorophyll, bilirubin, hemocyanin, hemoglobin, myoglobin, light-emitting: luciferin, Hematochromes (algal pigments, mixes of carotenoids and their derivates, carotenes, alpha and beta carotene, lycopene, rhodopsin, Xanthophylls, canthaxanthin, zeaxanthin, lutein, proteinaceous, phytochrome, phycobiliproteins, psittacofulvins, turacin and turacoverdin, melanin, urochrome, and flavonoids. In addition, algae pigments may also be suitable for inclusion within a plasma coating. These pigments may include; Chlorophyll a, b pigments and Chlorophyll c, -Ficobiliproteins, - Phycoerythrin, -Xantophyll, and -Fucoxantin pigments. Biosynthetic dyes may also beused, whereby bacteria, sugars or other organic matter may be used to generate a desired colourant or pigment.

[0200] Some pigments may be added to the coating which have a selective colour absorption. Such pigments may be synthesised or derived from plant pigments, flower pigments and biological structure pigments such as chromatophores. In addition, polymerisable chemistry, monomers, and precursors may also be generated from a biomass source for making a film or plasma polymerised coating

[0201] Bioplastic precursors may be sourced from biomass such as vegetable fats and oils, corn starch, straw, woodchips, sawdust, recycled food waste, seaweed and the like. Some bioplastic precursors are obtained by processing directly from natural biopolymers including polysaccharides (such as; starch, cellulose, chitosan and alginate) and proteins (such as; soy protein, gluten and gelatin), while others are chemically synthesised from sugar derivatives (such as; lactic acid) and lipids (oils and fats) from either plants or animals, or biologically generated by fermentation of sugars or lipids. Materials such as biobased polyethylene terephthalate, biobased polyethylene and degradable bioplastics, such as polylactic acid, polybutylene succinate, or polyhydroxyalkanoates may be produced from the above precursors or other biomass sources. These materials may be of particular use as monomers, precursors or plasma polymerisable coatings.

[0202] Polysaccharide-based bioplastics may be suitable for application to a substrate with the system, with such bioplastics including; starch-based plastics, cellulose-based plastics, chitosan and alginate. Chitosan may be of particular advantage as pigments and other biopolymers may be easily incorporated in a polymer formed therefrom and may be used in a wide range of packaging applications.

[0203] Bioplastics derived from starch will have properties which are dependent on its amylose / amylopectin ratio. For mechanical properties the pigment may include a higher ratio of amylose starch relative to amylopectin which may be advantageous. Mechanical property ratios are known within bioplastics manufacturing and are incorporated herein. Starch-based bioplastics may optionally be mixed or blended with biodegradablepolyesters to produce starch / polylactic acid, starch / polycaprolactone or starch / polybutylene adipate-co-terephthalate (commonly referred to as Ecoflex™). However, while the above starch bioplastics may be formed with the system, the system may have particular advantage in forming starch-based films which may be suitable for food packaging purposes, wrappings, packaging, papers, and composting items. These films may be formed from pigments including starch and thermoplastic polymers.

[0204] Another type of plastic which may be formed during a plasma polymerisation process in segment 500 may be protein-based plastics. These plastics may be formed from gluten, casein and soy bases. Aliphatic biopolyesters biopolyesters are mainly polyhydroxyalkanoates (PHAs) like the poly-3-hydroxybutyrate (PHB), polyhydroxyvalerate (PHV) and polyhydroxyhexanoate (PHH). In addition, polylactic acid (PLA) may be produced readily in the form of pigments, powders and granules. Using PLA bioplastics may allow for the formation of films, fibres, and packaging materials, for example. Polyhydroxyalkanoates are linear polyesters produced in nature by bacterial fermentation of sugar or lipids. Polyhydroxyalkanoates monomers may be readily used to form articles suitable for medical purposes. Polyamide 11, Polyhydroxyurethanes, lipid derived polymers, and other biomonomers and / or bioprecursors may be used with the system and may be provided in liquid or pigment form based on the application method.

[0205] Bio-derived polyethylene may be formed from ethylene monomer which can be derived from ethanol. Other alcohols may also be suitable to form a polymer when exposed to plasma. This may be of particular advantage when it is desired to carry a pigment in an aerosol or vapour, as the liquid portion of the aerosol or vapour may be an ethanol or ethylene monomer.

[0206] Generally, there are a number of categories of pigments which include: white pigments, coloured pigments, black pigments and special pigments. These pigments may be derived from natural sources or synthesised, or a combination of both. Particles which are insoluble in the application medium (varnishes, synthetic materials, printing inks,cosmetic formulations and construction materials) may also be used for forming a portion of a coating.

[0207] White pigments may impart a colour to a substrate 1 by diffuse reflection of light. Absorption pigments impart a colour through the absorption of light (additional diffuse reflection). Metallic pigments may create a shine from the reflection of light, and can be metal pigments. Special effect pigments, such as pearlescent pigments, may impart a colour, shine and / or interference effect through reflection and refraction of light (interference). These pigments properties may also be augmented by the plasma coating above and / or below the pigment to achieve a desired effect.

[0208] Special pigments may include transparent and functional pigments as well as effect pigments. Effect pigments may further be reduced to two subcategories which may include metal effect pigments and special effect pigments. Metal effect pigments may preferably comprise aluminium and / or copper-zinc alloys, with special effect pigments being used for pearlescent and interference pigments.

[0209] While pigments herein may be referred to as having a generally uniform diameter or uniform size, it will be appreciated that this is for simplicity and the surface of the pigment will generally be irregular or have an undulating surface from the production method. Pigment sizes suitable for the present application method and system may be in the range of 0.1µm and 200µm in diameter. However, effect pigments may be larger than pigments used for mere colourant. Effect pigments may have a size or diameter of between 5µm to 100µm, with these pigments having additional properties of being transparent, semi-transparent or light impermeable platelet-shaped particles. Other effects may also be imparted by pigments which may include one or more functional properties such as; magnetic, anti-corrosion, luminescent, antimicrobial, antiviral, flame retardant, hydrophobic, hydrophilic, self-cleaning, and oleophobic properties.

[0210] Effect pigments may generally be split into two categories which are metal effect pigments and special effect pigments. Both metal effect pigments and special effect pigments produce lustrous effects in the pigmented surfaces which is from the reflection oflight onto the pigment. In the special effect pigments pearlescence and interference are created by the division of the light from the light rays falling on the pigment surface because only a portion of the light is reflected while another part of the light penetrates into the transparent or semi-transparent particles and onto the deeper lying boundary layers from where it is reflected back. This results in the overlaying of light waves which, depending on their wavelength, are either intensified or diminished, which may be an interference.

[0211] Various types of coloured interference phenomena combined with gloss effects can be created by selecting pigments of metal oxide with respect to the refractive index of the binder (plasma polymerised coating) as well as the thickness of the plasma polymerised coating. The thicknesses of these coatings may be desired to be in the range of 5nm to around 500nm. Variations in the size of pigment particles, it may be possible to achieve varying effects from silk-matt to a very glossy transparent to a more opaque finish. This type of pigment application may use a sieve pigment application method, whereby pigment sizes are controlled, or may use a combination of laminations of pigment application and plasma polymerised coatings to achieve the desired effect.

[0212] Pigments may be selected with respect to its refractivity with respect to the thickness of the plasma polymerised coating, and / or the opacity of the plasma polymerised coating. Assessment of these properties may allow for bright interference colours or interference pigments to be applied to a substrate. A metallic sheen is, by contrast, produced by the simple reflection of light from metal platelets. The interactions using visible light that are fundamental to special effect pigments and metallic effect pigments.

[0213] Any predetermined pigments may be used within the plasma polymerised coating. At least one of a colourant or a functional pigment can be included within a plasma polymerised coating.

[0214] In a further embodiment, mica may be used as the pigment to be included within a coating. Mica is generally a naturally occurring mineral that can incorporate a desired shine to a colour. Further, mica pigments may be provided in any predetermined size ordesired colour, and are generally planar or plate-like in appearance. Mica pigments may be provided in a size range of 10 µm to 100µm across the surface with the thickness being in the range of 200nm to 10µm.

[0215] It may be desirable to include mica pigments as plasma coatings can be in the range of 100nm to 500µm in thickness, depending on the treatment time and parameters. Therefore, the thickness of the mica may allow for mica to be laid relatively parallel with the surface of a substrate to be coated and be relatively encapsulated or mostly embedded within the plasma polymerised coating.

[0216] Generally, mica pigments may be selected based on their opacity, transparency, and / or lustre. As a guide, mica particle sizes with a size of 15 µm or less may have a low lustre and a higher opacity, sizes of 2-25 µm may have a silky lustre and higher opacity, sizes 10-60 µm may have a pearl-like lustre with moderate to medium opacity, sizes 10- 125 µm may have a shimmering lustre and lower opacity towards transparent, sizes 20-150 µm may have a sparkling lustre and be generally transparent, and sizes 45-500 µm may have a more glittering lustre and may be very transparent. Plasma coatings used to fix these pigments may also impact the lustre or the opacity / transparency of the pigment. For example, the plasma coating may be adapted to reduce the lustre of pigments which have a natural or inherent high lustre, and thereby make the pigments appear more matt in appearance. Additional functionalities may also be imparted by certain pigments which can be embedded, encapsulated or otherwise bonded with a plasma coating.

[0217] Other metals and inorganic materials which may be used as pigments may be selected from the following group; titanium, aluminium, zinc, gold, cesium, copper; sulfates of calcium, strontium, barium; zinc sulfide; copper sulfide; titanium dioxide and barium zeolites; mica; talc; kaolin; mullite or silica. In addition, lead or mercury compounds may also have some use depending on the application. The average diameter of the metals deposited may be between 0.01 and 200 microns, preferably in the range 5 to 100 microns.

[0218] The textile receiving the metal coating may be inorganic particles having a first coating of a metal or metal compounds and a second coating layer of silica, silicates, borosilicates, aluminosilicates, alumina or mixtures thereof.

[0219] The inorganic particles, i.e., core material may be any of the oxides of titanium, aluminium, zinc, copper; calcium, strontium, barium and lead. Optionally as suggested, the materials may be sulfides or sulfates. It is preferred that a near pure metal or a metal alloy can be used to form a pigment for the pathogen disruptive layer. However, it will also be appreciated that other compounds may be used, such as silver nitrate (AgNO3), or titanium dioxide (TiO2). Other pigments commonly used in industry including organic and inorganic pigments may also be used if desired.

[0220] In one embodiment, pigments may form at least a part of a continuous coating or film which can conform to the general surface topography of the substrate 10. The pigments may be protected, covered, or have a functional coating applied thereto after deposition which can assist with reducing pigments from becoming dislodged from the substrate 10. Properties of functional coatings may include at least one of; flame retardant, UV absorbing, self-cleaning, hydrophobic, hydrophilic, and / or antibacterial. Other functionalisations may also be applied as is known in the art.

[0221] In other embodiments, the pigments may suitably be formulated in an appropriate carrier, coating or solvent such as water, methanol, ethanol, acetone, water soluble polymer adhesives, such as polyvinyl acetate (PVA), epoxy resin, polyesters etc, as well as coupling agents, antistatic agents. Solutions of biological materials may also be used such as phosphate buffered saline (PBS), or simulated biological fluid (SBF). The concentration of the pigments in the solution may in the range of from 0.001% (wt) to about 20% (wt). These pigments may then form a coating which can be applied to the substrate 10.

[0222] Flame retardants can reduce or inhibit flammability of the textiles by: Reducing the heat generation at combustion process, reduce flammable volatiles, modify pyrolysis reaction, form intumescent char layer, release water, release species like chlorinated, phosphorus, that act as an inhibitors in gas phase.

[0223] Particles which may be suitable for use for flame retardant coatings may include particles selected from the following group; Nano-clays, Zinc-borates, Carbon Nanotubes (CNT), Layered Double Hydroxide (LDH), Polyhedral Oligomeric Silsesquioxane (POSS), silicon dioxide (SiO2), and metal pigments. Optionally the SiO2may be nano-size. Any combination of particles may be utilised within a single coating. Optionally, a coating may be formed from several laminations such that the

[0224] Suitable nano-clays may be pigments of layered mineral silicates, which may be organised into several classes such as montmorillonite (MMT), and halloysite depending on chemical composition and morphology. Metal pigments may also be metal based pigments or oxides such as titanium dioxide (TiO2), Zinc Oxide (ZnO), Aluminium oxide (Al2O3), for example.

[0225] It may be preferred that the thickness of the coating applied is at least 100nm in thickness. It may be more preferred to select a coating in the range of 100nm to 100 micron for a fire-retardant treatment or coating.

[0226] Preferably the char yield of the substrate is improved with the inclusion of a fire- retardant coating. Coatings may preferably include particles such as fine particles or nano particles. After application of a coating a char yield test preferably exhibits an improvement of at least 1% increased char yield relative to a substrate without said treatment.

[0227] The thickness of the coatings may be in the range of 50nm to 900 micron. It may be more desirable to provide for a coating which is in the range of 150nm to 900nm. Preferably, the thickness of the coating to the particle size is in the range of 1:1 to 1:500, and more preferably, the thickness range of 1:2 to 1:200. It will be appreciated that the average thickness of the coating may be relative to the diameter of the particle within the coating.

[0228] It may be preferred that the particles within the coating are generally uniform in diameter or size. It will be appreciated that a distribution of particle sizes may be suppliedwithin the coating, wherein the distribution may comprise a size of particle at in a known size range and the remaining particles are larger or smaller than the known size range. For example, the particles within the coating may have a known particle size of 80% by volume with the remaining 20% of particles being of a size smaller or larger than the known particle size range. In another example, the particles within the coating may have a known particle size of 80% by weight with the remaining 20% of particles being of a size smaller or larger than the known particle size range.

[0229] Optionally, the particle coatings applied provide for a flame-retardant coating, or may be used in combination with a flame-retardant coating which has been applied via a chemical vapour deposition process. Preferably, any such deposition process is a plasma enhanced chemical vapour deposition process.

[0230] The particles for the flame-retardant coating may be applied in a lamination of the coating, or may be provided uniformly throughout the coating. Particles may be deposited on the surface of the substrate to be coated with a functional coating, or may be provided at the same time as the functional coating is applied to the substrate.

[0231] It is preferred that the thickness of the coating, or the build-up of coating at the contact end of the particle, is sufficient to embed the particle or fix the particle in a desired position. The thickness of the coating thickness may extend at least 5% of the height of the particle. Preferably, the particle is encapsulated by the coating.

[0232] Precursors that produce functional properties may optionally be used to compliment the pigment selection, or be used to provide a functional binder for the pigments such that other post-processing functionalisation treatments may be avoided or otherwise limited to reduce downstream resource consumption.

[0233] In yet another embodiment, an application device 310 may be similar to an inkjet printing device. These devices may be adapted to traverse the width, or a portion of the width, of the substrate such they may be used to apply a dispersion or colourant in a predetermined region within the segment 300. A plurality of dispersion devices 310 maybe adapted to traverse a predetermined span of the substrate, such that a complete or desired application of colourant may be applied by one or more printer heads.

[0234] Single pass dispersion application devices 310 can be used which will match the throughput of the system and allow for a dispersion to be evenly applied. Single pass printer heads may be static, and may provide a complete coverage for the substrate without the requirement for traversal of any of the application device 310, which may be printer heads, for the application of a dispersion.

[0235] Optionally, under the application devices 310, the substrate may be carried by a conveyor belt with an adhesive, or the substrate may be attracted to the belt via a vacuum system.

[0236] Unlike conventional dispersions and systems which apply dispersions, binders may not be required within, or may be significantly removed from, the dispersion of the present disclosure. As the pigments or colourants from the dispersion are to be fixed in place with a fixation plasma coating in segment 500, the dispersion may not require binders within. This is a significant improvement over conventional processes and dispersions. It will be appreciated that the weight % (wt%) of binders in dispersions for the present system may be reduced by 50% to 100% compared to other dispersions for similar applications. As such, it will be appreciated that the application of such dispersions may also yield an increase in deposition of dispersion, as dispersions with binders may be slower to apply relative to dispersions with low levels of binders or no binders.

[0237] Pigments which may be suitable for dispersions or dry pigment application may be selected from the following group: Carbon Black (Black), Copper phthalocyanine (Blue): Copper(II) phthalocyanine, Phthalocyanine green (G:green): copper hexadecachlorophthalocyanine, Carbazole Violet (Violet): 9,19-Dichloro-5,15-diethyl- 5,15-dihydrodiindolo[2,3-c:2',3'-n]triphenodioxazine, Quinacridone Magenta (Red 122): 5,12-Dihydroquinolino[2,3-b]acridine-7,14-dione, Arylide yellow pigments (different structures), Diarylide Yellow pigments (different structures), Dianisidine Orange: based on 3,3b-dimethoxybenzidine (o-dianisidine), Diarylide Orange: based on 3,3'-dichlorobenzidine : 3H-Pyrazol-3-one, 4,4′-[(3,3′-dichloro[1,1′-biphenyl]-4,4′- diyl)bis(2,1-diazenediyl)]bis[2,4-dihydro-5-methyl-2-phenyl, Aluminum pigments, ultramarine violet (Na8−10Al6Si6O24S2−4), copper pigments, Han purple; BaCuSi2O6, Cobalt pigments, Cobalt violet; cobaltous orthophosphate, Co3(PO4)2, Manganese pigments, Manganese violet; manganese ammonium pyrophosphate, NH4MnP2O7, Blue Pigments, Aluminium pigments, ultramarine; sodium-silicate (Na8−10Al6Si6O24S2−4), Cobalt pigments, Cobalt blue and cerulean blue; cobalt(II) stannate, CoOn·SnO2(n = 1 or 2), Copper pigments, Egyptian blue; calcium copper silicate (CaCuSi4O10), Han blue; a barium copper silicate, BaCuSi4O10, Azurite; cupric carbonate hydroxide (Cu3(CO3)2(OH)2), Iron pigments, Prussian blue; a synthetic pigment of ferric hexacyanoferrate (Fe7(CN)18), Manganese pigments, YInMn blue; a synthetic pigment (YIn1−xMnxO3), cadmium pigments, cadmium yellow (CdS) and viridian (Cr2O3), chromic oxide (Cr2O3), hydrated chromic oxide (Cr2O3·H2O), Cobalt green (CoZnO2), Copper pigments, cupric carbonate hydroxide (Cu2CO3(OH)2), cupric acetoarsenite (Cu(C2H3O2)2⋅3Cu(AsO2)2), cupric arsenite (CuHAsO3), copper salts, cupric acetate (Cu(CH3CO2)2), malachite (Cu2CO3(OH)2), terre verte and verona green K((Al·FeIII)(FeII·Mg)(AlSi3·Si4)O10(OH)2), monoclinic arsenic sulfide (As2S3), cadmium sulfide (CdS), lead chromate (PbCrO4), which also occurs as the mineral crocoite, potassium cobaltinitrite (K3Co(NO2)6), monohydrated ferric oxide (Fe2O3·H2O), lead antimonate, Pb(SbO3)2·Pb3(SbO4)2, Lead-tin-yellow; PbSnO4, Pb(Sn·Si)O3, Titanium pigments, Titanium yellow also called nickel antimony titanium yellow, nickel antimony titanium yellow rutile, NiO·Sb2O3-20TiO2, stannic sulfide (SnS2), cadmium sulfoselenide (CdS·CdSe), lead chromate and lead(II) oxide (PbCrO4·PbO), arsenic sulfide mineral (As4S4), cadmium selenide (CdSe), Sanguine, caput mortuum, indian red, venetian red, oxide red (Fe2O3), red Ochre; anhydrous Fe2O3, burnt sienna, raw sienna (Fe2O3·MnO2·nH2O), Minium (pigment), lead tetroxide (Pb3O4), mercury pigments, vermilion; synthetic and natural pigment; occurs naturally in mineral cinnabar (mercuric sulfide), (HgS), brown pigments, clay earth pigments (naturally formed iron oxides), raw umber; a natural clay pigment consisting of iron oxide, manganese oxide and aluminum oxide; Fe2O3·MnO2·nH2O·Si·AlO3, Raw sienna (Fe2O3·MnO2·nH2O); a naturally occurring yellow-brown pigment from limonite clay, Carbon black; ivory black, vineblack, lamp black (lampblack), iron pigments, mars black (iron black); Fe3O4, manganese pigments, Manganese dioxide (MnO2), titanium pigments, titanium black; titanium(III) oxide (Ti2O3), Antimony pigments, Antimony white; stibous oxide, antimony(III) oxide, Sb2O3, Barium pigments, Barium sulfate; BaSO4, Lithopone; BaSO4·ZnS, Lead pigments, Cremnitz white; basic lead carbonate ((PbCO3)2·Pb(OH2)), Titanium pigments, Titanium white; titanium dioxide (TiO2), Zinc pigments, Zinc white, zinc oxide (ZnO).

[0238] If the system is adapted to utilise a CMYK type colour system, there the following pigments may be most desired: Carbon Black (Black), Copper phthalocyanine (Blue), Quinacridone Magenta (Red 122), and Arylide or Diarylide yellow pigments. It will be appreciated that other pigments may also be used, but the above may be most preferred.

[0239] In yet a further embodiment, the dispersions which may be suitable for use with system may be a solvent formed with water. Water may be used to constitute between 5- 99% by weight (wt%) of the dispersion. A pigment can be used within said dispersion with a pigment colouration agent being between 0-60% wt% of the dispersion, depending on colour. Such pigment agents include, but are not limited to; Carbon Black (CAS 1333- 84-4 ), Pigment Red 122 (Cas 980-26-7), Titanium oxide White (CAS 13463-67-7), Pigment Blue 15:3 (Cas 147-14-8), Pigment Yellow 155 (Cas 68516-73-4). A wetting agent or dispersant are also used within the dispersion and may improve pigment dispersion and stability. These will be added in wt% between 0-30wt%. The Molecular weights of dispersants range from 50 – 500,000 g.mol-1, with chain lengths from 1 – 100,000.

[0240] The macromolecular arrangement of the polymers will vary from single monomer-based polymers to co-polymers consisting of multiple foundational monomer units. Example chemicals may be Ethylene and Propylene Glycols (CAS 107-21-1 / CAS 57-55-6 / 4254-15-3) and their polymers, Polysorbate (CAS 9005-65-6) of varying compositions, dimethylesiloxane-(Ethylene oxide) of various compositions, and polyethylene glycol-fatty acid co-polymers of varying constructions, however other chemicals can be used as desired.

[0241] Humectant(s) may be incorporated to improve coating application of a dispersion. These may be added in relevant quantities between 0-50wt%. The compounds are monomer or polymers which may be based on Glycerine / Glycerol (CAS 56-81-5 ), Polyethylene Glycol (200 – 600g.mol-1), Pyrrolidone (CAS 616-45-5), Alcohol ethoxylates, and Silicone polyethers. Other bases may also be used as desired. Other humectants may also be utilised to maintain a general dispersion fluidity, minimise nozzle clogging within any printing devices, and may impact evaporation during a drying process. Suitable humectants which may be included within a dispersion may be generally selected from the following group; glycerol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol having an average molecular weight between approximately 200 and 600, propylene glycol (1,2-propanediol), dipropylene glycol, and butylene glycol (including 1,3- and 1,4-butanediol isomers). Additional humectants such as sorbitol and glycereth-26 (polyethylene glycol-26 glycerin) may be incorporated to further enhance moisture retention and to optimise viscosity stability within the ink dispersion. Selection of humectant for a dispersion may be selected with respect to a desired evaporation rate during drying, interaction with textile substrates, compatibility with colourants and binders, and desired open-time of the printhead.

[0242] Cross-linkers may form between 0-20wt% of the dispersion, and may be Epoxy / oxiranes, or Diethlamine crosslinking agents, for example. Cross-linking agents may be selected to enhance pigment fixation, wash durability, and adhesion to textile fibres. Suitable cross-linking agents may be at least one of the following; multifunctional aziridines for reaction with carboxyl-functional binders; carbodiimides to impart hydrolytic stability; polyisocyanates, either blocked or unblocked, for covalent bonding to hydroxyl- or amine-functional polymers; and epoxy compounds for versatile cross-linking of hydroxyl, amine, and carboxyl groups. Additional cross-linkers may include melamine- formaldehyde resins for thermoset network formation, glyoxal and other aldehydes for cellulose and hydroxyl-containing binders, and zirconium, titanium, or aluminum coordination complexes for enhanced fastness. Silane coupling agents and hybrid cross- linkers, such as polycarbodiimide–silane systems, may further improve interfacial adhesion, wash resistance, and overall ink performance on a range of textile substrates. Itwill be appreciated that any desired crosslinkers may be present within a dispersion, however cross-linkers are only optionally included within a dispersion.

[0243] Biocide additives may also be used, which may include at least one of; Methyl- isothiazolinone (CAS 26172-55-4), 1,2-Benzisothiazol-3(2H)-one (CAS 2634-33-5), and 5-Chloro-2-methyl-4-isothiazolin-3-one (CAS 26172-55-4).

[0244] Aliphatic alcohols may optionally be included as co-solvents for pigment stability. These could be incorporated in wt% between 0-50wt%. The alcohols may consist of chain lengths of at minimum 1 carbon unit. Some examples include, but are not limited to, methanol (CAS 67-56-1), Ethanol (CAS 64-17-5), propanol (CAS 71-23-8), and butanol (CAS 71-36-3).

[0245] Plasma

[0246] The plasma generated by the plasma modules in the plasma segments may be preferred to be a dielectric barrier discharge. Plasma modules 510 within the plasma segments may be used to generate a plasma for a pre-treatment, surface activation or a plasma polymerisation process. A pair of parallel electrodes may be used within each module and charge a working gas to generate a plasma. The module may be split such that the a first electrode is relatively on one side of the substrate and the other electrodes is on the other side of the substrate. The substrate may be positioned relatively in the middle between these plates, or may be transported in contact with at least one of the modules. For example, a top and bottom electrode configuration may allow for the substrate to be transported while being in contact with the bottom electrode as this is the relative lower electrode.

[0247] Plasma-enhanced chemical vapor deposition (PECVD) is a thin film deposition technique typically used in various industries, including semiconductor manufacturing and optics. PECVD is used to deposit thin films onto a substrate surface. A precursor is supplied to the plasma reaction region in which the precursor are fractionated or otherwise broken-down, at least in part, and recombine and form a film at the surface of the substrate.The film may be a deposition of polymers or other species which have been formed within the plasma region.

[0248] Ionised gas consisting of positive ions, electrons, and neutral particles may be created by applying a strong electric field or radiofrequency energy to a working gas which may include the precursor.

[0249] Precursors can be used as a binder or a fixation chemistry for the fixation of a colourant or pigment from a dispersion. In some embodiments, the precursor may provide functional properties such that other post-processing functionalisation treatments may be avoided or otherwise limited to reduce downstream resource consumption.

[0250] Using the system 10, various polymer coatings, polymeric films, pigment coatings, and pigment treatments can be deposited onto a substrate 1. Non-limiting examples of chemistries, monomers and / or precursors may include at least one selected from the following group; acetylene, ethylene, isoprene, hexamethyldisiloxane (HMDSO), tetraethyloxy silane (TEOS), tetraethyloxy silica, diethyl dimethyl siloxane, 1,3-butadiene, styrene, methyl styrene , tetrafluoroethylene (TFE), methane, ethane, propane, butane, pentane, hexane, cyclohexane, acetylene, ethylene, propylene, benzene, isoprene, hexamethyldisiloxane, tetraethyloxy silane, tetraethyloxy silane, diethyl dimethyl siloxane, 1,3-butadiene m, styrene, methyl methacrylate, tetrafluoroethylene, pyrrole, cyclohexane, 1-hexene, allyl amine, acetylacetone, ethylene oxide, glycidyl methacrylate, acetonitrile, tetrahydrofuran, ethyl acetate, acetic anhydride, aminopropyltrimethylene triethoxyethane triethoxyethanoethoxytethenethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanoethoxyethane triethoxyethanethoxytriethoxyethanoethoxyethanoethoxy ethanol , tricarbonyl (cyclooctatetraen) iron, dicarbonyl (methylcyclopentadienyl) iron, dimer dicarbonyl (dicyclopentadienyl) iron, cobalt cyclopentadienyl cobaltacetylacetonate,nickel acetylacetonate, dimeti - (2,4-pentan-dionates) gold (III), nickel carbonyl, iron carbonyl, tin acetylacetonate, indium acetylacetonate, indium -tetramethylheptanedionate.

[0251] It may be desired to remove any moisture from the substrate before plasma treatment or applying a plasma coating. Alternatively, an oil may be used to disperse the colourant onto the article, whereby the oil may be polymerised and fixate the colourant to the article.

[0252] Oils which may be used are preferably biobased oils, however synthetic oils may also be used if desired. Oils may be used as a chemistry, monomer, and / or precursor. Biobased oils may be essential oils such as an oil selected from the following group; coconut oil, olive oil, sunflower seed oil, shea butter, jojoba oil, almond oil, grapeseed oil, rose hip seed oil, orange oil, allspice oil, ambrette seed absolute amyris oil, angelica root oil, anise oil, anise, star oil, anthopogon oil, atlas cedarwood oil, balsam fir oil, balsam, peru oil, basil oil, basil, holy oil, bay oil, bay laurel oil, beeswax absolute benzoin absolute bergamot oil, bergamot mint oil, black pepper oil, black spruce oil, blood orange oil, blue cypress oil, blue tansy oil, bois de rose oil, boronia absolute bursera graveolens oil, cade oil, cajeput oil, camphor, white oil, cananga oil, cannabis oil, caraway seed oil, cardamom oil, carrot seed oil, cassia oil, catnip oil, cedarwood, atlas oil, cedarwood, virginian oil, chamomile, german oil, chamomile, roman oil, chocolate peppermint oil, cilantro oil, cinnamon oil, cistus oil, citronella oil, clary sage oil, clove bud oil, coffee oil, common sage oil, copaiba balsam oil, coriander oil, cornmint oil, cubeb oil, cumin oil, cypress oil, cypress, blue oil, cypress, japanese oil, cypress, taiwan (formosan) oil, davana oil, dill oil, dalmatian sage oil, douglas fir oil, elemi oil, eucalyptus globulus oil, eucalyptus, lemon oil, eucalyptus radiata oil, fennel oil, fir, balsam oil, fir, douglas oil, fir, siberian oil, fir, silver oil, fragonia oil, frankincense oil, galbanum oil, geranium oil, geranium, rose oil, german chamomile oil, greenland moss oil, ginger oil, goldenrod oil, grapefruit oil, gurjum balsam oil, helichrysum gymnocephalum oil, helichrysum italicum oil, hemlock spruce oil, hemp oil, hinoki oil, hinoki, taiwan oil, ho leaf oil, ho wood oil, holy basil oil, hong kuai oil, hops oil, hyssop oil, ishpingo oil, immortelle oil, japanese cypress oil, jasmine absolute jatamansi oil, java pepper oil, juniper berry oil, kanuka oil, kunzea oil, labdanum oil,ledum oil, laurel leaf oil, lavandin oil, lavender oil, lavender, spike oil, ledum oil, lemon oil, lemon balm oil, lemon eucalyptus oil, lemongrass oil, lemon myrtle oil, lemon tea tree oil, lemon verbena oil, lime oil, linden blossom absolute mandarin oil, manuka oil, marjoram oil, may chang oil, melissa oil, myrrh oil, myrrh, sweet oil, myrtle oil, myrtle, lemon oil, nard oil, neroli oil, niaouli oil, nutmeg oil, oakmoss absolute ocotea oil, olibanum oil, opoponax oil, orange, bitter oil, orange, blood oil, orange, sweet oil, oregano oil, palmarosa oil, palo santo oil, parsley oil, patchouli oil, pepper, black oil, pepper, pink oil, peppermint oil, peppermint, chocolate oil, peru balsam oil, petitgrain oil, pimento berry / leaf oil, pine, pinyon oil, pine, scotch oil, pink pepper oil, plai oil, rambiazina oil, ravensara oil, ravintsara oil, rock rose oil, rhododendron oil, roman chamomile oil, rosalina oil, rose oil,, rose absolute and rose CO2 extract rosemary oil, rosewood oil, sage, clary oil, sage, common oil, sage, dalmatian oil, sage, spanish oil, sage, white oil, sandalwood oil, saro oil, scotch pine oil, siberian fir oil, silver fir oil, spearmint oil, spike lavender oil, spikenard oil, spruce, hemlock oil, spruce, black oil, star anise oil, sweet myrrh oil, sweet orange oil, tagetes oil, tangerine oil, tansy, blue oil, taiwan hinoki (taiwan cypress) oil, tea tree, common oil, tea tree, lemon oil, tea tree, new zealand oil, thyme oil, tobacco absolute tuberose absolute tulsi oil, valerian oil, vanilla absolute and vanilla co2 extract verbena, lemon oil, vetiver oil, violet leaf absolute virginian cedarwood oil, white camphor oil, white fir oil, white sage oil, wintergreen oil, xanthoxylum oil, yarrow oil, ylang ylang oil, yuzu oil. Other essential oils may also be used if desired. Shellac may also be used in some dispersions, and may be polymerisable in the plasma segment of the system.

[0253] It is preferred that any biobased oils have a double-bond, or are readily volatile such that they may be evaporated and / or vaporised. Evaporation, aerosolisation, and vaporisation of a chemistry, including biobased oils, may be passed into a plasma region generated by a plasma module 510 and subsequently polymerised. However, if the system is adapted to have an oil applied by the pigment applicator, the oil is preferred to have a double-bond within its structure to allow for polymerisation.

[0254] In at least one embodiment, an organic and / or inorganic coating may be applied. Inorganic coating precursors include pure metals, metal salts, oxides, nitrides, carbides, orcombinations thereof. In yet another embodiment, the system 10 may allow for various particles to be coated ranging in size from nanometre to micron. Coatings may be deposited by means of precursors that are either in a gaseous or liquid or solid state, but are preferably in a vaporised or aerosol state.

[0255] A plasma treatment may be suitable to activate the surface of a substrate, etch or round or otherwise smoothen a pigment, lower deposition temperatures of a substrate, and improve film quality adhesions in subsequent processes.

[0256] Introduction of oxygen gas may decrease a deposition rate of the fixation coating. However, the introduction of oxygen may also increase the coating thickness, during the same period of time compared with no oxygen gas. Oxygen gas may be found within air instead of using pure oxygen gas or a mixture of oxygen plus carrier gas such as argon. Air can be introduced into a plasma region at a desired rate and concentration or mixing ratio relative to the carrier gas and monomer.

[0257] Nitrogen, oxygen or air may increase the breakdown electric field during the plasma process which may impact the coating type produced. Further, the increase in breakdown electric field may cause a higher power draw from the power supplies for the plasma modules. This may be of benefit as the control of these power supplies may have a wider operational voltage for an optimal coating compared to chemistries which are not reacted in the presence of a nitrogen gas. The use of nitrogen gas may be in the range of 5%-20% by volume or by weight relative to the carrier gas and / or the primary reaction gas which may make up the balance. Other dosing of nitrogen and / or oxygen and / or air by volume or by weight relative to the carrier gas and / or the primary reaction gas which may make up the balance may be in the range of 0.5% to 40% nitrogen or 0.1% to 20% oxygen.

[0258] For colourant or pigment fixation the plasma modules may use a combination of carrier gas and a further gas, such as air or a controlled volume of at least one of nitrogen and / or oxygen.

[0259] The addition of air within the plasma region of the system may decrease the coating thickness as a function of time. For example, a pure argon treatment may apply a 100nm thick coating with parameter set A with a 1 minute exposure time, whereas an argon and air mix may yield a 80nm thick coating with parameter set A with a 1 minute exposure time. As such, control of the ratio of air to argon may be desired as the thickness of the coating can be augmented with different ratios of argon and air.

[0260] The volume of air may impact the coating type applied to the substrate, and also the thickness of the coating. In some embodiments, the volume of air may form a rougher type coating in which the oxygen may etch the surface of the coating. Silica like coating may also be formed with a controlled volume of air which may have stronger bonding with Si-O-Si groups being formed. With the introduction of air, the number of CH3bonds may be reduced or eliminated and may promote Si-OH groups to be formed within the plasma. Hydrophilic coatings may also be formed with the introduction of oxygen groups and therefore the control of the oxygen supplied to the plasma region is desire to be controlled.

[0261] In one embodiment, the precursor or chemistry which is used to form a coating may be HMDSO. The HMDSO may be carried to the reaction gap between two dielectric materials by a carrier gas. The carrier gas may be the same as the plasma gas, which is the primary gas used to generate a plasma in the plasma region, or may be a different type of gas which may assist with penning ionisation when striking a plasma. The carrier gas is used for carrying a predetermined volume of chemistry, monomer, and / or precursor to the reaction gap.

[0262] Herein, the terms “monomer”, and “precursor” may be collectively referred to as “chemistry”. The chemistry may be reacted, at least in part, within the plasma gas and form a coating on a substrate. Said coating may be a polymer or film which is formed during the on periods of the plasma, or within the afterglow immediately after the plasma is turned off. The formation of the coating on the substrate may be comprised of a covalently bonded structure, which may optionally include particles or nano-particles within the coating structure. These particles or nano-particles may be formed from thereaction of the chemistry rather than the from the presence of the pigment or particles deposited previously in the process.

[0263] In one embodiment, the plasma parameters for a system width of at least 1m is desired to be between 4kHz to 3MHz, or more narrowly between 4kHz and 500kHz, and may have an optional duty cycle of 0.2 / 0.8 (20%). The duty cycle will be understood to be the on / off time (in that respective order). Other duty cycles may include around 0.5 / 0.5 (50%), 0.4 / 0.6 (40%), 0.3 / 0.7 (30%), 0.25 / 0.75 (25%), 0.2 / 0.8 (20%), 0.15 / 0.85 (15%), 0.1 / 0.9 (10%), and 0.05 / 0.95 (5%). Other duty cycles may be any percentage between 1% to 100%, in which 100% is a continuous wave. The general on time may allow for active polymerisation of chemistry or precursor injected into the plasma region. The on / off time may be in the span of 1 second.

[0264] Voltages supplied per unit area of 0.01m2of an electrode may be in the range of 50V to 300V. The voltage may be directly supplied to the metal conductor of the electrode. Currents supplied to an electrode per unit area 0.01m2may also be in the range of 0.5A to 3.5A. The treatment surface of the plasma module is the dielectric face directly exposed to the plasma. The dielectric covering the metal electrode of the plasma module may be larger in surface area than the electrode. For example, the metal electrode may be 10cm in length, and the dielectric covering at least one surface of the metal electrode is 14cm, for example. In other embodiments, the electrode may be the same length and / or width as that of the dielectric.

[0265] In yet another embodiment, the metal electrode may be larger than the dielectric covering a portion of the metal electrode, such that the excess size of the metal electrode can be mounted into a holder, or other electrode support. In this configuration, it is desired that the support or holder abuts with the dielectric such that the metal electrode is not exposed to the plasma treatment region, and thereby reducing the potential for arching.

[0266] The power supplied per unit area (0.01m2) of treatment surface of a plasma module may be in the range of 60W to 300W for an electrode gap of between 0.1mm to3mm. The power may also be increased to between 80W and 600W per unit area (0.01m2) of treatment surface for a plasma module with gap sizes in the range of 3mm to 6mm.

[0267] At least one of; power, voltage, current, electrode gap, and frequency, may be varied depending at least one of; temperature of the electrodes, temperature of the supplied chemistry and / or carrier gas, substrate thickness, speed of the substrate, the chemistry to be reacted, the desired treatment, the reaction gas type, and the length of exposure of the substrate.

[0268] The system may be adapted to provide a minimum residence time for the substrate within the plasma segments. The residence time may be based on the function of the plasma coating being provided. For example, the residence time of the substrate within the plasma segments may be in the range of 30 seconds to 300 seconds. Longer treatment times may be used for a thicker coatings, or coatings which may have a polymerisation and a repolymerisation process. Longer treatment times may also be desired for lower power reactions to reduce potential substrate damage yet still supply a desired coating thickness to the substrate.

[0269] The flow rate of the gas per 10cm width of the plasma module may be in the range of 0.5L / min (litres per minute) to 30L / min. The gas supplied to the module may be carrying one or more chemistries or monomers which can be polymerised or reacted within the plasma reaction region of the plasma segments. Carrier gases, working gases and reaction gases may be any combination of gas from the group of; nitrogen, helium, argon, oxygen, hydrogen , neon, hydrogen, and xenon. Carrier gases, working gases and reaction gases may collectively be referred to as the “plasma gas” which is used to generate a plasma within the reaction gap of the modules.

[0270] The overall exposure time of the substrate being processed within the system may be governed by the on / off time or duty cycle of the system. Each module within the system may be adapted to have a discrete on / off time, or all modules may have the same on / off time. It may be advantageous to allow for modules to have a portion of off timerather than always be active as the chemistry or precursor may be replenished in the reaction gap during the off time and then reacted during the on time of the module.

[0271] The plasma polymerised coating formed on the substrate by the module 510 may be a protective coating which can be used to slow the diffusion of ions from pigments within, or may be a functional layer which provides for at least one functionalisation selected from the following group; flame retardant, UV absorbing, self-cleaning, hydrophobic, hydrophilic, and / or antibacterial. Other functionalisations may also be applied as is known in the art.

[0272] The pigment or plasma polymerised coating may be used to provide for at least one of a hydrophobic or hydrophilic functionality. Siloxane chemistry may be used to form a hydrophobic and / or hydrophilic coating on a substrate 1. Functionality of any such coating may be dependent on the thickness of the coating, the porosity of the substrate being treated and the pigments applied (if any).

[0273] Hydrophilic pigments may generally include transition metal or an oxide or complex thereof. These pigments as described herein may be included within the plasma polymerised coating and may be applied generally at the same time as the plasma coating, or as part of an in-line process.

[0274] Some examples of hydrophobic pigments may include; Manganese oxide polystyrene (MnO2 / PS), zinc oxide polystyrene (ZnO / PS) nano-composite, precipitated calcium carbonate, carbon nano-tube structures, silica nano-coating, and siloxane particles. Fluorinated silanes, fluoropolymer coatings, and siloxane coatings may be used as a binder for pigments while also providing a hydrophobic functionality.

[0275] Hydrophilic pigments may be carried in a solvent which may include ketones such as acetone or methylethylketone; alkanols such as ethanol or ethylene glycol, ethers such as diethylether; esters such as ethylacetate, and acetonitrile, at the time of application. Solvents may be used to form a portion of the plasma polymerised coating on the substrateafter exposure to plasma, or may be evaporated or substantially removed from the substrate before a plasma polymerised coating is applied to the article.

[0276] Hydrophobic performance, or superhydrophobic performance may be provided by the plasma polymerised coating alone, by the pigment alone, or by a combination of the two. Similarly, hydrophilic coatings may also be provided in a similar manner.

[0277] Soft hand feel may also be imparted with the use of at least one of pigments and / or a plasma polymerised coating. Soft handfeel is generally a metric for textiles or garments wherein the handfeel of the substrate or textile being treated generally does not change relative to the untreated substrate or textile handfeel, or softens the handfeel further. Softer handfeel may also relate to drapability of the substrate or textile. A primary advantage of using a plasma polymerisation to generate a plasma polymerised coating on a substrate may allow for a functionality to be imparted as well as providing for an improved handfeel. This may be particularly true with respect to plasma coatings which are applied with chemistry, monomer, or precursors being passed through a plasma region generated by a module 510 before being applied to a substrate.

[0278] Alternatively, thinner coatings may be applied by a mister, vaporiser or atomiser before being subjected to a plasma region to be polymerised. However, the difficulties of this application method may cause agglomeration or consolidation of the fluids applied which can cause uneven coatings to be provided under suboptimal conditions, or if the time between application and plasma treatment is too great.

[0279] Application of a plasma polymerised coating to the substrate is preferred to occur during a plasma exposure step, or allowing chemistry, monomer, or precursors to pass through a plasma region before application to the article. This is due to the fact that the thickness of the coating can be controlled more than with conventional coating application methods, such as dipping, knife coating, or spraying. Chemistry, monomer, or precursors entering into the plasma region, preferably in droplets, vapour or an aerosolised state may be readily fractionated and polymerised on the substrate to form a highly cross-linked structure which may then be deposited onto the article, wherein the coating or film canbuild or grow as desired. Development of a coating or film in this manner can reduce the overall consumption of material required to achieve a desired functional coating on a substrate 1.

[0280] A self-cleaning or anti-odour CuO, TiO2, and / or AgNO3pigment may be applied to a substrate 1 in which ions from the copper or silver may diffuse to the surface of the plasma polymerised coating the pigments are embedded within and promote an adverse environment for bacteria, microorganisms, viruses or other biological matter. Alternatively, the self-cleaning coating may be the primary coating applied to a substrate 1 which provides a self-cleaning coating. When exposed to sunlight these coatings may react with water to generate hydroxyl radicals. These radicals may break down organic molecules and microbes adsorbed on the surface of the coating. Fluids, such as water, may be applied to the coating which can be absorbed and allows for dust, dirt, oil, and other contaminants on the surface to be removed, or substantially removed. Other self-cleaning coatings may also be applied, and may have different activation or cleaning reactions, however it will be understood that any self-cleaning coating may be applied by the system 10.

[0281] Self-cleaning coatings may have applications for garments, medical devices, commonly touched articles, vehicles, aeroplanes and public facilities. Multiple coatings may be applied, or reapplied, to a substrate 1 such that desired properties can remove dirt, stains, oils, or other predetermined contaminants.

[0282] Photocatalytic self-cleaning fabrics use a variety of semiconducting materials, including titanium dioxide (TiO2), zinc oxide (ZnO), and silica (SiO2), among others. There are three distinct crystalline forms of TiO2: anatase, rutile, and brookite. TiO2 may be used as a photocatalytic hydrophilic pigment which is predominantly composed of rutile and anatase phases.

[0283] Some pigments may also be applied to a substrate which may be beneficial for anti-friction coatings. Solid lubricants may be distributed to the substrate which may act as the anti-friction coating. Lubricant pigments may also have utility in relation to corrosionresistance for articles or may have utility in relation to flame retardancy. Anti-friction coatings form a slippery film, which covers all surface roughness and thus optimises metal- to-metal, metal-to-plastic or plastic-to-plastic friction even under extreme loads and working conditions. Some examples of anti-friction pigments which may be included within a coating may include a material selected from the following non-exhaustive list; molybdenum sulfide (MoS), molybdenum disulfide (MoS2), PTFE, graphite, and special pigments.

[0284] UV absorbing or photoprotective pigments may include Mycosporine-like amino acids (MAAs). MAAs may be used to block or absorb UV-A and UV-B and absorb UV rays within the range of 310nm to 360nm. Melanin pigment may also be used to protect against UV. In addition, carotenoids and photopigments may be used to act as photo- protective pigments, as they quench oxygen free-radicals. Carotenoids and photopigments may also be used to supplement photosynthetic pigments that absorb light energy in the blue region.

[0285] In another embodiment, the pigment used in the process to form a coating or film on a substrate may comprise a metal oxide, for example, at least one metal oxide from the following group; SiO2, ZrO2, TiO2, Ta205, HfO2, ThO2, SnO2, VO2, In2O3, CeO2, CuO, CuS, FeCl2, ZnO, Nb2O5, V2O5, Al2O3, Sc2O3, Ce2O3, NiO, MgO, Y2O3, WO3, BaTiO3, Fe2O3, Fe3O4, Sr2O3, TiO3, Cr2O3, Mn2O3, Mn3O4, Cr3O4, MnO2, RuO2, or a combination of these oxides for example by doping the particles or by mixing the particles.

[0286] In yet a further embodiment, the system may be adapted to pre-treat or post treat a substrate. Pre-treatment or post-treatments may be any form of treatment the substrate may undergo to improve the interactions between at least one of the pigment and the plasma coating applied to the substrate 1. Any pre-treatment or post treatment may be provided outside of the system, but may be used to improve the plasma coating and pigment therein if desired. For example, a heat treatment process may be used to remove moisture from a substrate before treatment, or a heat treatment may assist with curing the plasma coating after processing. Other treatments may also be provided, such as a cleaning process, scouring process, ozone exposure, static cleaning, imparting a charge tothe article, exposing the substrate to a predetermined radiation and / or light, or a plasma treatment. Any such treatment imparted to the substrate may improve the durability of the coating, the functional performance of the coating and / or the pigment within the coating, the hardness of the coating, the handfeel of the coating, the coating thickness, the colour of the coating or the underlying article, the appearance of the coating, and the lustre of the coating.

[0287] Single- and double-sided coatings may also be provided by the system. Single sided coatings, for example on a substrate article, may be applied from a series of treatment modules which are positioned to face a single side of the article. This may be exemplified in Figure 1 wherein the treatments to the substrate being treated are all facing a first side. A second side of the substrate may be treated during the same process if there are treatment modules positioned to face the second side of the substrate article. Alternatively, the first side treatment modules may be adapted to urge, force or propagate a coating from the first side of the substrate through to the second side of the article, thereby treating both the first and second sides of the substrate 1.

[0288] In yet a further embodiment, the system may pass the substrate through the system and treat a first side of the article, and be adapted to re-feed the substrate through the system with the modules facing the second side of the substrate during re-feeding. This may involve turning the substrate before re-feeding, or a repositioning of one or more modules within the system to allow for the treatment of the second side.

[0289] With the system 1 able to coat a substrate with multiple treatments, or single sided treatments, the substrate may have one or more different functionalities applied to it. For example, a substate with a hydrophobic treatment on a first side of a substrate may have a hydrophilic coating on the second side of the substrate. This may be of particular advantage if the substrate is porous as the hydrophilic treatment may be used to wick and transfer moisture and the hydrophobic treatment may be used to transport and repel moisture in a desired manner. This may allow for a moisture wicking system which does not require the used of multiple membranes, adhesion process and complex structures to allow for a desired wicking effect. Other effects may also be anticipated whereby a firstside of a substrate may have a hydrophobic treatment applied thereto, and a hydrophilic treatment applied relatively on top of said hydrophobic treatment, and the second side of the substrate may have a further hydrophobic and / or hydrophilic treatment applied thereto such that intermediate layers of the coatings applied thereto may be adapted for the transport of moisture.

[0290] Disperse dyes are generally non-ionic and have low solubility in water. These disperse dyes are generally suitable for some synthetic materials, such as polyester, Rayon™, acrylic and polyamides. It will be appreciated that within the art, the dyeing or colouration of polyester and acetate fibres may generally only be achieved with the use of disperse dyeing techniques. Disperse dyes are generally known to not be suitable for use with natural fibres or natural materials.

[0291] Disperse dyes discussed herein may alternatively be disperse inks, and any reference herein may be interchangeable. Disperse dyes may be provided to a substrate in a solution or liquor, and the colourant may precipitate out to remain on the substrate to provide colour.

[0292] Negative charges present or that may build up on the surface of some hydrophobic fibres, such as those of synthetic fibres, generally make non- ionic inks and dyes, such as disperse dyes, the only suitable method for colour application as these are not influenced by the surface charge present on fibres.

[0293] The dyeing of hydrophobic fibres with disperse dyes may be considered as a process of dye transfer from liquid solvent to a solid organic solvent. Disperse dyes may be added to water with one or more surface active agents to form an aqueous dispersion. The general insolubility of disperse dyes allows for the dyes to leave the liquor readily and be applied to fibres of the substrate, or any other substrate. After the dye has been applied to the substrate a plasma process may be used to treat the substrate with the disperse dyes, which may allow for a polymerisation or bonding of the disperse dye, or may be suitable to change the ionic nature of the disperse dye. The plasma process may also be used to at least partially vaporise the dye, which may be of particular relevance for sublimation,which may then penetrate into the fibres or the substrate allowing for a suitable colour transfer. Heat and / or pressure, which may allow for sublimation to occur, may optionally be used after a plasma treatment such that the energy of dye molecules are increased and the colour transfer is fixed to the substrate completely. However, it will be appreciated that the heat treatment process may be foregone with the use of a plasma treatment step. A heating and / or pressure step, which may allow for sublimation to occur, may be used before a plasma treatment step also.

[0294] As discussed above, the plasma treatment may also be used to alter the surface morphology of the colourants precipitated by the disperse dyes applied to the substrate. The modifications may allow for a colour change, such as changing colour depth for example, or may be used to improve handfeel of the final coloured substrate.

[0295] Any plasma treatment which is used with respect to disperse dyes may be a plasma coating process, wherein a plasma coating is applied to capture the dye or colourant between the substrate and the coating. As the coating may conform to the general shape of a surface of the substrate, the dyes may be retained relatively in place before a heat treatment process. Preferably, any plasma coating applied is a hydrophobic coating, such that the dyes may be urged into the substrate by being repelled from the coating. With respect to plasma coatings which are hydrophilic, this may provide an affinity for solutions to more fully adhere, penetrate or spread into the substrate which may assist with fixation of the disperse dyes after a heating process.

[0296] In another embodiment, a plasma treatment step may be an etching step, wherein the disperse dyes are bound, embedded or partially trapped within the etched portions of the substrate. As the plasma etching is conducted, the depth of the etch may be provided based on the disperse dye molecule or colourant size. This is to say the etch may be larger or generally be the same size as that of the colourant to be deposited onto the substrate.

[0297] During heating of dye liquor the substrate, or fibres thereof, may swell or expand to some extent and penetration of the dyes may be achieved. In this way the dye molecule is urged into the amorphous regions of the fibres. Once within the fibre of the substrate,the dye molecules are held by hydrogen bonds and / or Vander Waals force, or may be held or physically entrapped in place with partial bonding caused by the plasma treatment.

[0298] In yet another embodiment, the process for colour application is the same as conventional application methods, however a post-plasma process may be used after the heating step. The post plasma process may facilitate bonding between the dye and the surface of the substrate, or may assist with fixing the dyes within the structure of the substrate more effectively.

[0299] It will be appreciated the surface energy of the substrate may also be altered which may allow for a better adherence with the disperse dyes, which is not possible with conventional processing techniques. Furthermore, the use of plasma at atmospheric conditions generally provides for a reduction of cost relative to other plasma processing which require vacuum chambers, partial pressures, or controlled environments.

[0300] In a further embodiment, a plasma process may be used before the application of a disperse dye, such that the surface energy of the substrate can be modified. As an example, while it will be readily appreciated within the art that plasma treatments may convert low energy surfaces to higher energy surfaces by removing hydrogen from the surface and attaching oxygen-containing species, if a generally inert plasma environment is used, the attachment of oxygen or higher energy species may be avoided or reduced. This may be of particular advantage as higher energy substrates optionally have a reduced surface energy, or removal of particular species on the substrate, which may allow for bonding of the dyes more readily with the surface of the substrate.

[0301] Disperse dyes may also be vapourised to allow for a colour transfer from the dispersion to the substrate during a plasma process. As disperse dyes are generally volatile with temperature exposure, a plasma treatment may exploit the volatility of the dyes and provide a novel mechanism to reduce the energy required for causing a desired volatility for colour application.

[0302] In another embodiment, a plasma treatment may be used in place of a mordant to allow for fixation of dyes or inks with a substrate, such that the colour imparted becomes insoluble. A plasma coating may also be used to cause a reactive surface of the disperse dye and cause a bond with the plasma coating which may also bond with the substrate. This is not possible with conventional techniques as the dyes will not become reactive in a similar manner, nor could similar covalent bonding be affected.

[0303] Furthermore, the plasma treatment process may be used to treat substrates which may experience notable shrinkage at higher temperatures. The plasma process employed by the present disclosure may expose the substrate to temperatures between 20°C and up to around 110°C. More preferably, the temperatures are generally around an upper region of about 70°C-95°C which can start the vaporisation of the dyes or may allow for a bonding of the dyes without needing to achieve the conventional temperatures of between 105°C to around 130°C, or higher. This may avoid shrinkage of the substrates, particularly with respect to acrylics or polyamides.

[0304] In yet a further embodiment, the application of a disperse ink or dye may occur during the plasma treatment process, such that the ink or dye is polymerised (or bonded), or otherwise exposed to a plasma before being applied to the substrate. This may be of particular advantage as penetration of the plasma treatment to reach pre-coated or pre- applied dyes or inks may be difficult or yield a less than desired bond between the dye and the substrate.

[0305] In yet another embodiment, the substrate may be functionally altered by a plasma treatment process wherein the substrate may be made hydrophobic such that the disperse dyes may behave in a similar manner as when applied to a man-made substrate which to which disperse dyes are conventionally used.

[0306] In at least one embodiment, a disperse dye may form at least part of a dispersion, such that the disperse dye may be applied to a substrate. Unlike typical applications for disperse dyes, the process of the present disclosure may be suitable to fix the disperse dyes to natural fibres and not just man-made fibres. This is of particular use with respect tocotton, hemp, flaxseed, wool, and bamboo type fibres. Other natural fibres may also be used within the spirit of the disclosure and the application of disperse dyes therefore may be for natural and / or synthetic substrates without modification of the overall process. The present disclosure processes may be suitable to fix disperse dyes to heat sensitive synthetic materials such as polyamide substrates without exposing the substrates to high temperatures which exceed 100°C. In this case the dyes may be fixed to the surface of the fibres without the need for an additional heating step to cause the diffusion of the dyes into the substrates.

[0307] It will be appreciated that the plasma treatment may optionally be used to sublimate the disperse dyes on the substrate, however it is generally preferred that the plasma treatment process is independent of a sublimation process.

[0308] Method

[0309] Referring to Figure 8, there is shown a method for treating a substrate 1. The method involves the following steps:

[0310] Step 1: Unwinding a substrate from an unwinder and tensioning the substrate 1 to a desired tension. The substrate 1 may have a lead-in material which can be used to pull through the system the substrate 1 to be treated. Similarly, a lead-out material may be fixed to the substrate 1 such that there is minimal wastage from processing.

[0311] Step 2: An optional step wherein the substrate 1 is passed through an atmosphere controlled segment wherein atmosphere external the system is limited from ingress into the system segments.

[0312] Step 3: An optional step wherein if a primer segment is included with the system the substrate is exposed to the optional primer treatment. Primer treatments may be any number of treatments including; a heat treatment to remove moisture form the substrate, or applying a primer layer to which the dispersion in the application segment is applied to, exposing the substrate to a UV treatment for removing biological material from thesubstrate 1, a vacuum apparatus to remove material from the surface of the substrate before a dispersion is applied, a misting or wetting apparatus to increase a moisture content of the substrate, and a sterilisation device for sterilising the substrate before a dispersion is applied. Any number of these primer treatments may be used before a dispersion is applied to said substrate 1. Optionally, a plasma pre-treatment may be used to activate a surface or etch a surface of the substrate. Plasma pre-treatment may be used to attach functional groups to the surface which may be used to improve the adhesion between the dispersion or pigment to be applied.

[0313] Step 4: Applying a dispersion to the substrate 1 in the application segment. More than one application segment may be included within the system for applying one or more dispersions. The application segment may utilise any method known within the art and discussed herein to apply a dispersion to the substrate 1. The dispersion is preferably adapted to carry one or more colourants such that the colourants can be imparted to the substrate 1 to colour said substrate 1.

[0314] Step 5: After the dispersion has been applied to the substrate, the substrate 1 enters into the heating segment in which the substrate may optionally be exposed to a heating device. The heating device may be a ceramic heating device or an IR heating device which may rapidly heat the substrate in a controlled manner. In an alternative method, the heating may take place by passing the substrate over a heated drum or heated plate which may outgas or desorb fluids within the substrate which have been applied and / or adsorbed during the application segment 300.

[0315] Step 6: The substrate is passed into a plasma segment to receive a plasma coating. The plasma coating is provided to the substrate in the plasma segment and is formed from the chemistry supplied to the reaction gap between the electrodes during plasma processing. The plasma polymerisation process may be adapted to only polymerise the chemistry supplied within the plasma segment and may not be suitable to polymerise any residual dispersant on the substrate. Optionally, the energy provided to the plasma reaction gap is sufficient to etch and / or polymerise any residual dispersion the substrate and alsopolymerise a chemistry provided to the reaction gap, in which the chemistry is supplied from the plasma segment 500.

[0316] Each module used to apply a plasma coating may be adapted to apply the same treatment, or a combination of treatments which may include one or more different types of coatings. Preferably the plasma segments are used to apply a fixation coating to the substrate to fix the residues and pigments of the dispersion, or fix the pigments, to the substrate. Modules which are adapted to apply a different coating relative to a module which has come immediately before it may be used to apply a new layer of coating on the substrate, such that laminations are applied which may assist with producing shear planes, abrasion resistant coating layers or layers with a different glass-like structure.

[0317] Optionally, at Step 6 a plasma pre-treatment or post-treatment step may also be applied by the segment 500 such that only a working gas is provided to a module and the coatings deposited previously are subjected to a further plasma which may assist with finishing a surface of the coating deposited or applying a desired functional group depending on the working gas. For example, a functional working gas may include a nitrogen, or an oxygen, or other reactive gas. A working gas which will not apply a functional group may be an inert or noble gas which forms the plasma.

[0318] Step 7: Optionally repeating steps 1 to 6 for the other side of the substrate such that both sides are treated.

[0319] In another embodiment, as shown in Figure 9, the substrate it may be desired that step 4 is the application of a dry pigment or colourant and the heating step is not required, such that Steps 1, 4 and 6 are required in a process, with steps 2, 3, 5 and 7 are optional.

[0320] The above steps form a part of an embodiment of a process for colouring and / or functionalising a substrate 1. It may be desired in some embodiments to only functionalise the substrate and thereby the process method includes Step 1 followed by Step 6, and may optionally include Steps 2, 3 and 7. In this embodiment, Step 7 is repeating steps 1 and 6, and may include repeating Steps 2 and 3 also.

[0321] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms, in keeping with the broad principles and the spirit of the invention described herein.

[0322] The present invention and the described preferred embodiments specifically include at least one feature that is industrial applicable.

Claims

CLAIMS 1. A method for colouring a substrate, the method comprising; applying a colourant to the substrate; exposing the substrate to a plasma to fix the colour to the substrate; and wherein the colourant is fixed to the substrate by a coating fluid delivered to the substrate after application of colour.

2. The method as claimed in claim 1, wherein a surface of the colourant is physically modified by the plasma.

3. The method as claimed in claim 1 or claim 2, wherein the colourant is delivered to the substrate in a dispersion 4. The method as claimed in claim 3, wherein the dispersion is at least partially removed before being exposed to a plasma.

5. The method as claimed in claim 2, wherein fluids of the dispersion are removed leaving the colourant of the dispersion on the substrate before being exposed to a plasma.

6. The method as claimed in any one of the previous claims, further having the step of heating the substrate after applying the colourant to remove moisture from the substrate.

7. The method as claimed in any one of the previous claims, comprising the step of supplying a monomer to the plasma such that the monomer is polymerised to form a polymer over the colourant.

8. The method as claimed in claim 6, wherein the polymer bonds to the substrate and the colourant.

9. The method as claimed in any one of the previous claims, wherein the coating fluid is polymerised by the plasma to form a coating and the colourant is at least partially embedded within the coating.

10. The method as claimed in claim 8, wherein the coating is of a thickness which encapsulates the colourant within the coating.

11. The method as claimed in any one of the previous claims, wherein the plasma is formed at a pressure between 95kPa to 110kPa.

12. A system for applying a colourant to a substrate, the system comprising; a processing line with a colourant application device; arranged down the processing line relative to the colouration application device is a plasma module; and wherein the colourant application device is adapted to apply a colourant to the textile and the plasma module is used to apply a coating to the colourant to fix said colourant to the substrate.

13. The system as claimed in claim 12, wherein between the colourant application device and the plasma module the processing line includes a heating system adapted to evaporate dispersion from the substrate.

14. The system as claimed in any one of claim 12 and claim 13, wherein the colourant application device is selected from the following group; a digital printer, an inkjet printer, a textile printer, a hydraulic spray device, an atomisation spray device, and an electrostatic applicator.

15. The system as claimed in any one of claims 12 to 14, wherein the plasma module is operable in the pressure range of 95kPa to 105kPa.

16. The system as claimed in any one of claims 12 to 15, wherein the plasma module is provided with a first electrode and a second electrode in which the first and second electrodes are arranged to be parallel, in which the electrodes have a dielectric material.

17. The system as claimed in any one of claims 12 to 16, wherein the plasma module is adapted to apply a functional finish.

18. The system as claimed in any one of claims 12 to 16, wherein the plasma physically modifies a surface texture of the colourant on the textile.

Images